The United Nations Security Council held an emergency meeting Sunday to discuss Iran’s attack on Israel. The meeting ended without any action by the council.

“Now is the time to defuse and de-escalate,” U.N. Secretary-General António Guterres said. “Now is the time for maximum restraint.”

Israeli Ambassador Gilad Erdan told the council: “Last night, the world witnessed an unprecedented escalation that serves as the clearest proof for what happens when warnings aren’t heeded. Israel is not the boy who cried wolf.”

Iranian Ambassador Saeid Iravani said: “Iran’s operation was entirely in the exercise of Iran’s inherent right to self-defense. This concluded action was necessary and proportionate.”

U.S. deputy ambassador Robert Wood said after the meeting ended, “There has to be a Security Council response to what happened last night.”

The Israeli military has activated two brigades of reserve troops for “operational activities” in Gaza.

In a post to X, Israeli Defense Force (IDF) spokesman Daniel Hagari said the recruitment of these forces “will allow the continuation of the effort and readiness to defend the State of Israel and maintain the security of the residents,” per a translation of the original post.

The announcement comes ahead of an expected invasion of Rafah, a city in the Gaza Strip that Israel says is the last major stronghold still controlled by Hamas.

It’s also home to roughly one million people, including many Palestinians who fled to the city earlier in the conflict. The expected invasion has drawn condemnation from some Western leaders.

White House National Security Spokesman John Kirby on Sunday called on China to “do more” to help de-escalate tensions in the Middle East after Iran’s April 13 drone and missile strike.

“Look, I won’t dispute the fact that China can do more, China should do more in the Middle East,” Mr. Kirby said when asked about U.S. efforts to cajole China into helping with de-escalation given China’s close relationship with Tehran.

“We’ve asked them to use that influence to a positive effect,” he added, acknowledging that China has not followed through on U.S. requests to that end.

But he argued that China is “not the leader in the region that they’d maybe like to be”—the United States is.

Speaking about how Israel should respond, Mr. Kirby said that’s "up to the Israelis to decide.”

A senior White House official said today the United States will not assist in any retaliatory strikes by Israel.

Israeli President Isaac Herzog said that Iran’s Saturday strike on Israel was tantamount to “a declaration of war” by the Persian state, but insisted that Israel is still “seeking peace.”

Mr. Herzog delivered the remarks during an interview with Sky News.

“We were attacked last night from four corners of the Middle East with proxies shooting at us, firing ballistic missiles, drones and cruise missiles," Mr. Herzog said. "This is like a real war. I mean, this is a declaration of war.”

However, Israel is nevertheless “seeking peace” and to avoid an escalation, Mr. Herzog said.

Still, he called on world leaders to “make it clear” that Iran’s actions were “unacceptable,” saying it’s “about time the world faces this empire of evil in Tehran.”

The Israeli war cabinet is currently meeting behind closed doors to discuss a response to the attack.

The United States will not participate in a counter-strike against Iran should Israel choose to retaliate for an attack on its territory last night, according to the White House.

“We’re committed to defending Israel. We would not be a part of any response they do. That’s a very consistent [U.S.] policy,” the senior administration official told reporters during a call on Sunday.

Comments came after some media reports stated earlier that President Joe Biden warned Israeli Prime Minister Benjamin Netanyahu that he would not support retaliatory action against Iran during a phone call on Saturday.

“Our aim is to de-escalate regional tensions. We do not want a broader regional conflict,” the official added.

When asked if President Biden’s phone call influenced his Israeli counterpart's decision not to proceed with a counter-attack, the official declined to confirm but did add that the president had tried to "slow things down."

“Israel will make its own decisions. But we made our views known,” he said, noting that the phone call took place last night during an “incredibly intense period.”

“It was a period of heightened emotion. And I think the president had a discussion about trying to slow things down,” he said. “And I think Israel has to think through carefully what it does next.”

During the call, a senior defense official also provided an update on the “unprecedented” attack against Israel.

Iran launched “300 munitions, including over 100 ballistic missiles as well as cruise missiles and UAVs,” a senior defense official said.

“These attacks were launched from locations in Iran, Iraq, Syria, and Yemen against Israeli territory. And it was the first ever direct attack on Israel from Iranian soil,” he said.

Leaders of the G7, after a virtual meeting, issued a statement expressing support for Israel and condemning Iran’s April 13 drone attack.

“We, the Leaders of the G7, unequivocally condemn in the strongest terms Iran’s direct and unprecedented attack against Israel,” the group said. “We express our full solidarity and support to Israel and its people and reaffirm our commitment towards its security.”

The group of international leaders accused Iran of “further stepp[ing] toward the destabilization of the region and risk[ing] provoking an uncontrollable regional escalation."

“This must be avoided,” the statement said, with G7 leaders vowing to “continue to work to stabilize the situation and avoid further escalation.”

The statement demanded that Iran and its proxies cease attacks on Israel, and said that G7 leaders “stand ready to take further measures now and in response to further destabilizing initiatives.”

Additionally, the leaders said they would continue to work toward an “immediate and sustainable ceasefire” and the release of Israeli hostages held by Hamas.

Lawmakers are divided on the proper response to Iran’s attack on Israel over the weekend.

Some, like Sen. John Kennedy (R-La.) and Sen. Lindsey Graham (R-S.C.) are calling for a strong and swift response to the drone strikes, which Iran said were carried out in retaliation for a suspected Israel strike on an Iranian diplomatic building in Syria in early April.

“If we turn the other cheek to them, we’re going to get it in the neck,” Mr. Kennedy said during an appearance on “Fox News Sunday.”

“We need to stand with Israel. It’s very clear. We’re not at war with Hamas, or Hezbollah or Yemen. Those are all surrogates for Iran. Those are … prostitutes, the pimp is Iran. Israel is at war with Iran,” Mr. Kennedy said. “Iran hates Americans. Iran hates Jews, Iran wants to kill Americans and Jews.”

Mr. Graham wrote in a post on X, “It is long past time for the Iranian regime to pay a heavy price.”

Rep. Don Bacon (R-Neb.) during an appearance on NewsNation’s “The Hill Sunday” warned against a “weak” response.

Other lawmakers, meanwhile, have expressed concerns that the conflict could escalate.

That was the concern expressed by Sens. Chris Coons (D-Dela.) and J.D. Vance (R-Ohio) during appearances on CNN’s “State of the Union.”

Mr. Vance said, “I certainly think there is a real fear of escalation,” but he blamed the attack on weak deterrence measures by the United States.

“I think if we want to reestablish deterrence, the most important thing is not how we or Israel respond to this attack. It’s how we focus in the long term on rebuilding our country,” Mr. Vance said. “People aren’t worried that we’re not thumping our chest enough. I know that’s the John Bolton response to this.”

White House adviser John Kirby said that Israeli Prime Minister Benjamin Netanyahu was “very grateful” for United States military support after Iran attacked Israel last night.

President Joe Biden and Mr. Netanyahu held a phone call last night over the attack, which Iran has said was in retaliation for a suspected Israel strike on an Iranian diplomatic building in Syria in early April.

During that call, coming near the end of the attack, President Biden reportedly “congratulate[d] Prime Minister Netanyahu for an incredible military achievement.”

Speaking about the phone call on CNN’s “State of the Union,” Mr. Kirby said, “The prime minister was very grateful for the support that President Biden offered and demonstrated in supporting Israel. And the president made it clear that the self-defense of Israel is something we take seriously, and we will continue to take that seriously.”

President Biden had earlier made public declarations that such an attack was imminent. After Iran carried out the strikes, which were largely intercepted by a joint effort by Israeli, U.S., and other allied forces, President Biden denounced the incident as a “brazen attack.”

It’s currently unclear whether and how Israel intends to respond.

“I certainly won’t speak for Prime Minister Netanyahu and what they’re thinking and whether and how they’re going to respond, because, really, that’s up for them to decide,” Mr. Kirby said.

Israel announced at 7:30 a.m. on Sunday morning that it has reopened its airspace after its airport authority closed all airports due to Iran's attack overnight.

Iraq and Jordan, which saw Iranian drones flying through their airspace toward Israel, were also forced to close their airspaces late on Saturday. Both reopened on Sunday morning. Lebanon also said it had reopened its airspace.

All airlines either cancelled or suspended flights to and from Tel Aviv on Saturday night until further notice.

But on Sunday morning, Israel's flag carrier El Al said it had resumed operations and was “working to stabilise the flight schedule as soon as possible.”

In comments to Iranian state TV, the commander of Iran's Islamic Revolutionary Guard Corps (IRGC) Major General Hossein Salami warned that any future attacks by Israel against Iranians—officials or civilian—will face the same response by the IRGC, with the attacks overnight marking a "new chapter" in Iran's fight against Israel.

His comments were echoed by IRGC chief of staff Major General Mohammad Bagheri, who told state TV, "Our response will be much larger than tonight's military action if Israel retaliates against Iran."

He added that Washington had been warned that any U.S. actions responding to Iran's attack would result in U.S. bases being targeted.

IDF spokesman Rear Adm. Daniel Hagari said in an update early Sunday morning that "99 percent of the threats launched towards Israeli territory were intercepted" overnight in joint defense efforts by Israel and its allies—"a very significant strategic achievement."

Mr. Hagari said that Iran launched over 300 different threats of various types toward Israel on Saturday night; 170 drones, more than 30 cruise missiles, and over 120 ballistic missiles. Only ballistic missiles were among the threats that crossed into Israeli territory, the IDF said.

Nevatim Air Force Base suffered "minor damage to infrastructure" and remains operational.

"The Iranian threat met the aerial and technological superiority of the IDF, along with a strong fighting coalition—which together intercepted the overwhelming majority of the threats."

No deaths have been reported by Israel. Minor injuries and panic attacks were reported by Israel's emergency service for 31 people as they made their way to emergency shelters.

Israel's Prime Minister Benjamin Netanyahu said on X following Iran's attack, “We have intercepted, we have contained. Together we shall win.”

Israel also took fire from ongoing tensions with Hezbollah in southern Lebanon. A barrage of rockets was fired by the Iranian proxy on northern Israel early Sunday morning. The IDF said that it responded with strikes on Hezbollah targets across Lebanon with its fighter jets.

Following reports on anonymous comments allegedly made to NBC late Saturday night, the Pentagon released another statement addressing Iran's attack on Israel.

Pentagon Press Secretary Maj. Gen. Pat Ryder said in the statement that Defense Secretary Lloyd Austin had spoken with Israeli Minister of Defense Yoav Gallant for "a second time today to reiterate ironclad U.S. support for Israel's defense in light of Iran's unprecedented attack from Iranian territory."

Hours earlier, U.S. media NBC published unverifiable reports from anonymous sources on the content of private talks as described to the outlets by "top U.S. officials."

According to NBC's reporting, "Some top U.S. officials are concerned Israel could do something quickly in response to Iran’s attacks without thinking through potential fallout afterward, according to a senior administration official and a senior defense official.

The report continued, "President Joe Biden has privately expressed concern that Israeli Prime Minister Benjamin Netanyahu is trying to drag the U.S. more deeply into a broader conflict, according to three people familiar with his comments."

The senior administration official then allegedly added that, "The White House believes Israelis are not looking for a wider war or a direct war with Iran, but U.S. officials can’t be certain."

Mr. Ryder said in his statement that, "Secretary Austin and Minister Gallant praised the extraordinary defensive measures and strong cooperation undertaken to defeat this Iranian attack against Israel.

"Secretary Austin again stated clearly that Israel could count on full U.S. support to defend Israel against any future attacks by Iran and its regional proxies," the statement read.

U.S. Secretary of State Antony Blinken said in a statement early Sunday morning that while the United States does not seek escalation, it will continue to support Israel's defense.

"The United States condemns Iran’s attack on Israel in the strongest terms. While we do not seek escalation, we will continue to support Israel’s defense, and as the President made clear, we will defend U.S. personnel," he said.

He said that in the hours and days ahead, he will be consulting with allies and partners in the region and around the world regarding a response to Iran's attack.

Mossad said in a statement early Sunday morning that Hamas has rejected its humanitarian deal for a temporary ceasefire in return for its release of Israeli hostages.

In a statement on behalf on Mossad, the prime minister's office that Hamas's Gaza chief, Yahya Sinwa, is "continuing to exploit the tensions with Iran" after the hostage release and ceasefire talks in Cairo failed to produce a compromise.

"It has been over a week since the Cairo meeting—Hamas has rejected the outline that was tabled by the mediators," the statement read. "The rejection of the proposal by the three mediators, which included the most significant flexibility on Israel's part, proves that Sinwar does not want a humanitarian deal and the return of the hostages, is continuing to exploit the tension with Iran, and is striving to unite the sectors and achieve a general escalation in the region.

"Israel will continue to strive to realize the objectives of the war with Hamas with full force, and leave no stone unturned to return the 133 hostages from Gaza forthwith," Israel said.

After more than six months of war with Israel in Gaza, the negotiations remain deadlocked, with Hamas demanding that any agreement must end Israel's war to eradicate it from Gaza.

"We ... reaffirm our adherence to our demands and the national demands of our people; with a permanent ceasefire, the withdrawal of the occupation army from the entire Gaza Strip, the return of the displaced to their areas and places of residence, intensification of the entry of relief and aid, and the start of reconstruction," the Islamist faction said.

President Joe Biden released another statement late Saturday before midnight.

"Earlier today, Iran—and its proxies operating out of Yemen, Syria, and Iraq—launched an unprecedented air attack against military facilities in Israel. I condemn these attacks in the strongest possible terms.

"At my direction, to support the defense of Israel, the U.S. military moved aircraft and ballistic missile defense destroyers to the region over the course of the past week. Thanks to these deployments and the extraordinary skill of our servicemembers, we helped Israel take down nearly all of the incoming drones and missiles," he said.

"I’ve just spoken with Prime Minister Netanyahu to reaffirm America’s ironclad commitment to the security of Israel. I told him that Israel demonstrated a remarkable capacity to defend against and defeat even unprecedented attacks—sending a clear message to its foes that they cannot effectively threaten the security of Israel."

President Biden said that his administration will convene with G7 leaders on Sunday to "coordinate a united diplomatic response to Iran’s brazen attack."

"My team will engage with their counterparts across the region. And we will stay in close touch with Israel’s leaders," he added.

Following requests from Israel's ambassador, an emergency meeting of the U.N. Security Council has been scheduled for 4 p.m. ET on Sunday, according to a schedule released late on Saturday.

U.N. Secretary-General Antonio Guterres has condemned Iran for its attack, saying he was "deeply alarmed about the very real danger of a devastating region-wide escalation."

President of the U.N. General Assembly Dennis Francis said the attack by the Islamic Republic of Iran on Israel "compounds the already tense and delicate peace and security situation in the Middle East."

"I strongly call upon all parties to exercise the utmost restraint to avoid further escalation of tension in the region. This is a moment that calls for wise and prudent judgement, in which the risks and extended risks are very carefully considered."

Israel has long been critical of the United Nation's approach to engaging governments like Iran. Iran is currently the chair of the U.N. Conference on Disarmament despite its continuous breaches of U.N. nuclear agreements.

U.N. Watch director Hillel Neuer said in a post on X, "Iran's unprecedented attack on Israel with 350 missiles and suicide drones constitutes a blatant act of aggression in violation of Art. 2 of the United Nations Charter. Why are the heads of Amnesty, HRW, and UNHRC completely silent?"

Reuters contributed to this report.

Iran's mission to the United Nations in New York said in a series of statements posted on X on Saturday night ET, which was early Sunday morning in Israel, that its retaliatory attack on Israel has concluded.

"The matter can be deemed concluded," it said.

It went on to threaten more severe responses going forward should Israel "make another mistake," while telling Israel's ally, the United States, to stay away.

"It is a conflict between Iran and the rogue Israeli regime, from which the U.S. MUST STAY AWAY!"

The United States military assisted Israel to shoot down many of the incoming Iranian drones and missiles. Jordanian jets also shot down many Iranian drones as they flew across northern and central Jordan, Israel media reported.

The Iranian regime said its attack on Israel was "[c]onducted on the strength of Article 51 of the U.N. Charter pertaining to legitimate defense" and that "Iran’s military action was in response to the Zionist regime’s aggression against our diplomatic premises in Damascus" in which seven military targets were killed, alongside six Syrian nationals who were in the area at the time.

Iran’s Revolutionary Guard Corps (IRGC) confirmed that a top commander of its elite Quds Force—and his deputy—were among those killed in the strike.

"This action was in the exercise of Iran's inherent right to self-defense as outlined in Article 51 of the Charter of the United Nations, and in response to the Israeli recurring military aggressions, particularly its armed attack on 1st April 2024 against Iranian diplomatic premises, in the defiance of Article 2(4) of the Charter of the United Nations," it added.

Days earlier on April 11, Iran's U.N. mission blamed the United Nations for its attack.

"Had the U.N. Security Council condemned the Zionist regime’s reprehensible act of aggression on our diplomatic premises in Damascus and subsequently brought to justice its perpetrators, the imperative for Iran to punish this rogue regime might have been obviated," it said in a post.

Since 2015, Iran and Hezbollah have both maintained a military presence in Syria, where they operate in coordination with the Syrian army and government.

Israel accuses Iran and Hezbollah of using their military assets in Syria to conduct cross-border attacks on Israeli targets.

The IDF said early Sunday morning that it was lifting its order for Israelis to stay near their safe rooms.

Adam Morrow contributed to this report.

Israel’s Ambassador to the U.N. Gilad Erdan has demanded the United Nations condemn Iran over its assault on Israel tonight and designate the IRGC a terrorist organization.

“Iran has violated the U.N. charter and has shown that it is a threat to global peace and security. Where is your voice?? Where is your condemnation?? Wake up!!!” Mr. Erdan said on X.

In a letter on Saturday to the president of the U.N. Security Council, Mr. Erdan requested an emergency meeting. A tentative meeting is being discussed for 4 p.m. ET, a diplomat told Reuters, speaking on condition of anonymity.

The Saudi Foreign ministry called on the security council to "fulfill its responsibility in maintaining international peace and security" in a statement late Saturday.

"The Kingdom urges all parties to exercise maximum restrain and to protect the region and its people from the dangers of war.

"This region is crucial for global peace and security, and the Council must act to prevent this crisis from escalating, which would have grave consequences if it expands."

Reuters contributed to this report.

In an update, Israeli military spokesman Rear Adm. Daniel Hagari said that while Iran's large-scale coordinated attacks were still occurring, "we have intercepted the vast majority of incoming missiles by Israeli systems."

"So far, we have intercepted and are continuing to intercept dozens of attack drones, as well as cruise missiles and ballistic missiles outside of Israel's border," he said, referring to Israel's long-range Arrow Aerial Defense System. A number of Iranian missiles fell inside Israeli territory, causing minor damage to a military base with no casualties. Only one little girl has been hurt and we hope she will be well."

The 7-year-old was seriously wounded by shrapnel falling after Israel's air defenses intercepted an invading Iranian projectile.

Mr. Hagari said Israel had counted over 200 different kinds of killer drones, ballistic missiles, and cruise missiles that were fired at Israel by forces of the Iranian regime. More than 10 were cruise missiles.

"We are still in the event, our planes are still in the air intercepting targets, and we are ready for any threat that will come to Israel. We will do everything we need, everything to defend the State of Israel."

Iran had been threatening to attack Israel since an airstrike last week widely blamed on Israel killed two Iranian generals in Syria. Israel has not commented or claimed responsibility for that attack.

Israel's airspace has been closed as of Sunday 12:30 a.m. Flights have been canceled until further notice.

The Associated Press contributed to this report.

President Joe Biden said he met his national security team about Iran's attacks against Israel.

"Our commitment to Israel’s security against threats from Iran and its proxies is ironclad," he wrote in a social media post.

Former President Donald Trump from a campaign rally in Pennsylvania said, "I want to say God Bless the people of Israel. They’re under attack right now. America supports Israel and we send our support to everyone in harm's way.

"This is an attack that would not have happened [if we were in office] ... we will return the world to peace through strength, and it'll happen very quickly. I will revive American strength abroad and we will restore American strength at home," he said.

High Representative of the EU for Foreign Affairs and Security Policy and European Commission Vice President condemned the attacks.

"The EU strongly condemns the unacceptable Iranian attack against Israel. This is an unprecedented escalation and a grave threat to regional security," Josep Borrell Fontelles said.

"Canada unequivocally condemns Iran’s airborne attacks against Israel. We stand with Israel. After supporting Hamas’ brutal October 7 attack, the Iranian regime’s latest actions will further destabilize the region and make lasting peace more difficult," Canadian Prime Minister Justin Trudeau said in a statement. “These attacks demonstrate yet again the Iranian regime’s disregard for peace and stability in the region. We support Israel’s right to defend itself and its people from these attacks."

Prime Minister of the United Kingdom Rishi Sunak released a statement condemning "in the strongest terms the Iranian regime’s reckless attack against Israel."

"These strikes risk inflaming tensions and destabilising the region. Iran has once again demonstrated that it is intent on sowing chaos in its own backyard. The UK will continue to stand up for Israel’s security and that of all our regional partners, including Jordan and Iraq. Alongside our allies, we are urgently working to stabilise the situation and prevent further escalation. No one wants to see more bloodshed," he said.

France’s Foreign Minister Stephane Sejourne condemned Iran’s attack in a post on X.

“In deciding to take this unprecedented action, Iran has reached a new level of destabilization and is risking a military escalation,” he said. He reiterated France’s commitment to Israel’s security.

While on a state visit to China, German Chancellor Olaf Scholz warned Iran against escalating tensions in the region.

"The attack on Israeli territory that Iran launched tonight is unjustifiable and highly irresponsible. Iran risks a further escalation in the region. Germany stands by Israel and we will discuss the situation with our allies," he said on X.

Australia, the Czech Republic, Denmark, Mexico, the Netherlands, and Norway also condemned Iran's attack.