Israel-Gaza-Lebanon updates: Nasrallah killed for tying Hezbollah cause to Gaza war

President Joe Biden told reporters outside the White House on Wednesday night that the U.S. was "able to generate significant support from Europe, as well as the Arab nations" for a 21-day cease-fire between Israel and Hezbollah to head off a full-scale war in Lebanon.

"It's important this war not widen," the president said. "I'll have more to say about it tomorrow."

In a call with reporters just before the president landed, senior administration officials described the proposal as a "breakthrough" they hoped would produce momentum in Lebanon and in stalled talks between Israel and Hamas in the Gaza Strip

"This is an important breakthrough on the Lebanon side, given all that has gone on there, particularly over the last few weeks," a senior administration official said. "But you know, we will try to use the space that provides wisely on all on all fronts."

The officials indicated that a response is expected over the next several hours.

"I guess the parties are going to respond for themselves to the call, but I can share that we have had this conversation with the parties and felt this was the right moment, based on the call, based on our discussion, they are familiar with the text and again, we'll let them speak to their actions of accepting the deal in the coming hours," a senior administration official said.

Officials said they'd been negotiating with Lebanon nonstop for the past 48 hours, and that its leaders there were aware they speak for "everything that happens on that side of the border," indicating that they will accept the deal on behalf of Hezbollah.

"So our expectation is when the government of Lebanon or when the government of Israel both accept this, this will carry and be implemented as a ceasefire on both sides, on both sides of the blue line, for the period of the 21 days," an official said.

-ABC News Cheyenne Haslett

A U.S. official confirmed to ABC News that the small number of additional American military personnel deployed to the Middle East are on the Mediterranean island of Cyprus, where they are planning for "non-combatant evacuation operations" in Lebanon.

The planning remains a precautionary measure, the official said. ABC News understands that between 12 and 24 American troops are involved in the preparations, not all of whom are special operations personnel.

Pentagon deputy press secretary Sabrina Singh said Wednesday she could not confirm the exact number of personnel deployed.

"What I can tell you is that we are sending a small number of additional U.S. military personnel forward to augment forces that are already in the region," she told reporters.

"I'm just not going to be able to provide you more specifics," she added. "I know it's frustrating, but I'm just not going to be able to confirm more."

-ABC News' Luis Martinez

Danny Danon, Israel's permanent representative to the United Nations, told reporters on Wednesday that his nation would "prefer a diplomatic solution" to its unfolding conflict with Hezbollah in Lebanon, but that "if it fails to return our residents to their homes, then we will use all means at our disposal."

"We are entirely focused on achieving our objectives, which in the north is the return of our displaced citizens who have become refugees in their own country," Dannon said.

"Do not mistake a peaceful nation for a defenseless one. We have the means, we have the capabilities to achieve this goal."

Danon again expressed that Israel was "open to ideas" to avoid a full-scale war.

"But you know, we are very honest about it. Our goal is to push Hezbollah from the fence, allow the residents to come back to the communities, and I hope we'll be able to achieve it without using our military capabilities," he said.

Israel is already conducting an extensive airstrike campaign across southern Lebanon and the Bekaa Valley, as well as limited airstrikes in the capital Beirut and elsewhere.

Israeli actions have killed more than 650 people -- including at least 50 children -- and wounded more than 1,700 others since Monday, according to Lebanese authorities.

Danon declined to weigh in on whether progress had been made towards a pause, but said negotiators "know exactly what we expect."

-ABC News' Shannon Kingston

Iran "will not remain indifferent in case of a full-scale war in Lebanon," Iranian Foreign Minister Abbas Araghchi told reporters Wednesday on the sidelines of the United Nations General Assembly in New York City.

Araghchi also warned that Israel's "crimes will not go unpunished," and said the Middle East region "risks full-scale conflict" if the U.N. Security Council does not "act now to halt Israel's war and enforce an immediate ceasefire."

"The path to de-escalation is clear," Araghchi said. "Israel must immediately stop its attacks on Gaza and Lebanon. Without a ceasefire in Gaza, there will be no guarantee of peace in the region."

"The Security Council must act now to halt Israel's war and enforce an immediate ceasefire, and by that, to save innocent lives. If not, the region risks full-scale conflict and history will hold Israel's enablers, especially the United States, responsible."

"Iran will not remain indifferent in case of a full-scale war in Lebanon," the diplomat added. "We stand with the people of Lebanon with all means."

-ABC News' Ellie Kaufman