The Biden administration has been holding talks with Israel, Lebanon and intermediaries for Hezbollah aimed at reducing current tensions on the Israeli-Lebanese border and restoring calm there longer-term by moving Hezbollah forces away from the frontier, according to Lebanese and Israeli officials, and other participants in the talks.

The diplomatic effort is being led by Amos Hochstein, a senior White House adviser who oversaw talks last year that resulted in a historic agreement between Israel and Lebanon that resolved long-running maritime border disputes between the countries. Hezbollah, the most powerful political and military force in Lebanon, backed the agreement after initially expressing opposition and threatening to attack Israel’s gas rigs.

The immediate focus of the discussions has been to prevent cross-border skirmishes between Israel and Hezbollah — fueled by Israel’s war against Hamas in Gaza — from escalating into an all-out conflict, said the officials, who spoke on condition of anonymity to discuss the sensitive deliberations.

Mr. Hochstein and other U.S. officials have passed messages to Israel, Lebanon and Hezbollah, warning them that the risk of escalation is extraordinarily high and encouraging them to exercise maximum restraint to avert a war that could draw Iran, other regional militant groups, and the United States into the conflict.

The United States does not negotiate directly with Hezbollah, which it has designated a terrorist organization. The Lebanese foreign minister, prime minister and speaker of Parliament have been acting as intermediaries for Hezbollah, according to a senior Lebanese official.

In addition to its efforts to contain the immediate risk of escalation, the Biden administration has been discussing with the parties the parameters of a longer-term agreement to increase stability along the border so that tens of thousands of displaced civilians in northern Israel and southern Lebanon feel safe enough to return to their homes after the war in Gaza ends.

One guiding principle supported by the Biden Administration is seeing the Lebanese Armed Forces become the sole border force on Lebanon’s side of the frontier, thus pushing Hezbollah forces away from the border with Israel.

According to participants in the talks, Israeli officials have sent mixed messages about the distance Hezbollah fighters would have to move north of the border to allow Israeli civilians to return to their communities in northern Israel. One Israeli proposal called for Hezbollah forces to move at least five kilometers, or about three miles, north of the Israeli-Lebanese border — to reduce the chances that the group could follow Hamas’s example and send large numbers of fighters into Israel to kill and kidnap Israeli civilians. Another called for them to move eight kilometers.

Biden administration officials have not taken a formal position on how far Hezbollah forces should be required to move north of the Israeli-Lebanese border, to preserve their flexibility in the negotiations, but they believe the distance may need to be more than five kilometers.

U.S. officials hope that Hezbollah, which they say is sensitive to local public opinion, will abide by an agreement that puts members of the Lebanese Armed Forces on the border. They point to Hezbollah’s decision to go along with the maritime agreement and to surveys that show that more than 80 percent of the Lebanese public do not want a conflict.

The Israeli prime minister’s office declined to comment. Hezbollah officials did not respond to a request for comment.

American officials have told their Israeli and Lebanese counterparts that restoring calm on the Israeli-Lebanese border will not be possible until Israel ends its war in Gaza, because Hezbollah and other groups are unlikely to stop firing munitions into Israel as long as that conflict continues.

Another objective of the talks has been finding ways to resolve longstanding border disputes between Israel and Lebanon.

Lebanese officials were encouraged by Mr. Hochstein’s mediation in the maritime talks and approached the U.S. Embassy in Beirut over the summer to propose that he reprise his role to see if Israel and Lebanon could settle disputes over 13 border points.

Mr. Hochstein began exploratory talks with the parties in the weeks before Oct 7.

Some elements of the Lebanese government and the armed forces were eager to proceed expeditiously with the talks in the belief that an agreement to demarcate the border would strengthen their hand within Lebanon, where Hezbollah — which is also part of the government — is the dominant power.

Hezbollah has long said that it needs to stay armed in order to win back Lebanese land it views as occupied by Israel. While the group has had moments of popular support in Lebanon, in more recent years some of the population has come to see the group as being as corrupt as other parties, and as using Israel’s occupation of Lebanese land as an excuse to stay armed.

“Of course Hezbollah is sensitive to its local constituents, but only up to a certain point. Hezbollah is not going to do something that endangers its own survival or the credibility of its own deterrence or its military posture,” said Emile Hokayem, a senior fellow for Middle East security at the International Institute for Strategic Studies.

Israeli leaders initially showed less enthusiasm than their Lebanese counterparts in pursuing the talks, according to participants.

As Mr. Hochstein was holding preliminary discussions with the parties over the 13 border points in dispute, Hamas militants in the Gaza Strip on Oct. 7 launched deadly attacks into Israel, prompting Israel to invade the territory to destroy the group.

In a show of solidarity, Hezbollah fighters began firing rockets into northern Israel. In retaliation, the Israeli military launched strikes against Hezbollah positions in southern Lebanon.

As tensions rose along the border, Israeli leaders considered launching a major air assault against Hezbollah forces in Lebanon, according to Israeli and U.S. officials.

Israeli officials who pushed for the air assault argued that Israel should cripple Hezbollah before the Lebanese group, which Israel has long considered a far more powerful adversary than Hamas, opened fire on Israel.

Biden administration officials urged Israeli leaders not to carry out the proposed air assault, pointing to intelligence that showed that Hezbollah, and its allies in Tehran, did not want a war with Israel. American officials also assessed that Hezbollah would be able to quickly recover from the initial shock of the Israeli strike and launch huge volleys of rockets at strategic targets across Israel.

U.S. officials said Israeli leaders were deeply divided themselves about the wisdom of carrying out the proposed air assault, and they agreed to instead pursue a diplomatic solution with Hezbollah, based on the border demarcation talks that Mr. Hochstein agreed to mediate before Oct 7.

Shortly after the Biden administration secured Israel’s agreement, Mr. Hochstein began shuttling between Israeli leaders and their counterparts in Lebanon, according to participants in the talks.

The most pressing focus of the talks was to keep the cross-border fire between Israel and Hezbollah at the lowest levels possible.

Since Israel started its war against Hamas militants in the Gaza Strip, Hezbollah has fired more than 1,000 missiles, rockets, mortars, drones and other projectiles into Israel, an Israeli military spokesman, Lt. Col. Jonathan Conricus, said on Monday. As a result, at least nine Israeli soldiers and four civilians have been killed.

American officials say Hezbollah has shown a measure of restraint, noting that the Israeli death toll has been relatively low because the group has purposefully fired many of its rockets into unpopulated areas.

The Israeli military’s retaliatory strikes into Lebanon have been more deadly — more than 100 of Hezbollah’s fighters and more than a dozen civilians have been killed, according to the Lebanese authorities.

Still, some Israeli officials say that Hezbollah’s threat to Israel must be dealt with if the United States is unable to reach a diplomatic deal.

Hezbollah’s cross-border attacks created the legitimacy for Israel to act “to remove Hezbollah’s forces north of the Litani River through political means or, alternatively, through military means even at the cost of a full-scale war to destroy the threat from Lebanon,” said Naftali Granot, a former deputy director of the Mossad, Israel’s foreign intelligence service.

Under United Nations Resolution 1701, which was reached following the 2006 Israel-Hezbollah war, the Lebanese militia group was supposed to withdraw its forces north of the Litani River. The U.N. has stated that Hezbollah is violating the resolution. In addition, the U.N. has accused Israel of routinely violating Lebanese air space.

Lebanese officials hope that, if an agreement is reached, Israel will have to curb its air incursions into Lebanese territory.

If U.S. diplomatic efforts fail and a full-scale war breaks out between Israel and Hezbollah, the results for both sides could be catastrophic. Hezbollah rockets could severely damage Israeli airports, seaports and much of the country’s electric grid. The Israeli response, in turn, would likely destroy huge swaths of Lebanon.

Jake Sullivan, President Biden’s national security adviser, said during a visit to Israel last week that Israeli citizens had to be able to return to their homes and feel secure doing so. But he said that the United States believed “that threat can be dealt with through diplomacy and does not require the launching of a new war.”