President Biden and his team, hoping to avoid further escalation leading to a wider war in the Middle East, are advising Israel that its successful defense against Iranian airstrikes constituted a major strategic victory that might not require another round of retaliation, U.S. officials said.

The interception of nearly all of the more than 300 drones and missiles fired against Israel on Saturday night demonstrated that Israel had come out ahead in its confrontation with Iran and proved to enemies its ability to protect itself along with its American allies, meaning it did not necessarily need to fire back, the officials said.

Whether Prime Minister Benjamin Netanyahu of Israel and his government will agree to leave it at that was not immediately clear. Although damage from the attack was relatively light, the scope of the strikes went well beyond the small-bore tit-for-tat shadow war between Iran and Israel in recent years, crossing a red line by firing weapons from Iranian territory into Israeli territory. Had defenses not held, scores or hundreds could have been killed.

Emotions were running high among Israeli officials during phone calls with American partners late into the night, and the pressure to fire back was consequently strong. The U.S. officials, who spoke on the condition of anonymity to describe sensitive discussions, stressed that the decision was ultimately up to Israel. Israeli jets early Sunday hit structures in Lebanon controlled by Hezbollah after the Iranian-backed militia sent two explosive drones into Israel, but it was not clear how related that was to the Iranian airstrike.

Mr. Biden spoke with Mr. Netanyahu on Saturday after the Iranian attack and repeated his “ironclad commitment” to Israel’s security. While the president did not publicly disclose any advice he offered, in a statement released after the call, he hinted at a desire for restraint.

“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,” Mr. Biden said.

He vowed to convene the leaders of the Group of 7 major industrial democracies on Sunday to coordinate a “united diplomatic response,” a sign of his preferred path forward after the attack. The United Nations Security Council will also meet in an emergency session on Sunday.

“Taken together, @JoeBiden’s message is designed to gently persuade #Israel not to pursue further escalation,” Robert Satloff, the executive director of the Washington Institute for Near East Policy, wrote on social media.

That will generate criticism of Mr. Biden from conservatives, who quickly went public urging a powerful military reprisal against Iran — not only by Israel, but by the United States, as well. “We must move quickly and launch aggressive retaliatory strikes on Iran,” Senator Marsha Blackburn, Republican of Tennessee, said in a statement posted online.

Speaker Mike Johnson blamed the Iran strike partly on the Biden administration because of its “undermining of Israel and appeasement of Iran” without mentioning that he himself has so far failed to permit a floor vote on bipartisan legislation passed by the Senate providing security aid to Israel and Ukraine. Representative Steve Scalise of Louisiana, the House Republican leader, said that “in light of Iran’s unjustified attack on Israel,” the House this week would consider aid to Israel, but he gave no details.

The eruption between Israel and Iran came at a time of great tension between Mr. Biden and Mr. Netanyahu. In a call only 10 days ago, the president threatened to rethink his support for Israel’s war in Gaza if Mr. Netanyahu did not do more to alleviate civilian suffering in the enclave, leveraging American backing for the first time since the Oct. 7 Hamas-led terrorist attack on Israel.

At the same time the two leaders clashed, Israel had just executed an airstrike against the Iranian Embassy complex in Damascus, Syria, killing seven Iranian officers involved in covert operations in a move that threatened the escalation Mr. Biden had long feared. Even so, the president made clear that his support for Israel’s security was still unwavering and warned Iran not to respond.

American and Israeli officials spent the past few days coordinating military operations in case Iran did act, and Mr. Biden ordered aircraft and ballistic missile defense destroyers to the region. Administration officials were elated at the results on Saturday as U.S. and Israeli forces knocked down nearly everything thrown at Israel by Iran, including more than 100 ballistic missiles, a feat that one official said may be unmatched in military history. Jordan intercepted projectiles crossing its airspace, saying it was guarding its own security.

Even though Iran did little tangible damage, it signaled after Saturday night’s strike that it was ready to stand down — and clearly hoped to avoid direct engagement with the United States. “The matter can be deemed concluded,” the Iranian Mission to the United Nations said in a statement. “However, should the Israeli regime make another mistake, Iran’s response will be considerably more severe. It is a conflict between Iran and the rogue Israeli regime, from which the U.S. MUST STAY AWAY!”

While the number of drones and missiles fired at Israel was extraordinary, it did not go unnoticed that Iran telegraphed its intentions to attack for more than a week and announced the launch of the drones hours before they actually reached Israeli territory, giving plenty of notice for defenses. Some analysts interpreted that as meaning that Iran wanted to put on a show of force to save face after the killing of its officers, but did not want a full-fledged war with Israel or the United States.

The situation was reminiscent of when in 2020 President Donald J. Trump ordered an airstrike in Iraq to kill Maj. Gen. Qassim Suleimani, who led the powerful Quds Force of the Islamic Revolutionary Guards Corps. Iran retaliated by firing missiles at well-defended U.S. bases in Iraq with relatively little damage, though about 100 U.S. military personnel were injured. It then sent a private message saying it was done. Mr. Trump chose not to retaliate, and fears of a cycle of escalation faded.

In the days leading up to Saturday’s attack on Israel, Mr. Netanyahu warned Tehran not to act, saying, “Whoever hurts us, we hurt them.” But because Israel was not especially hurt, Mr. Netanyahu may have some room to declare victory and move on. Israeli officials were not clear on their intentions.

“The campaign is not over yet — we must remain alert and attentive to the instructions published by the I.D.F. and Homefront Command,” said Defense Minister Yoav Gallant, referring to the Israel Defense Forces. “We must be prepared for every scenario. Having said this, we have thwarted the most significant wave” of the attack, “and we did so successfully.”

The American argument was that because Israel also successfully took out those senior Iranian officers in Damascus two weeks ago without paying a significant price, another round of military action could be deemed unnecessary.