The release, which could begin within the next several days — barring last-minute hitches — could lead to the first sustained pause in conflict in Gaza.

A detailed, six-page set of written terms would require all parties to the conflict to freeze combat operations for at least five days while an initial 50 or more hostages are released in smaller batches every 24 hours. It was not immediately clear how many of the 239 people believed to be in captivity in Gaza would be released under the deal. Overhead surveillancewould monitor movement on the ground to police the pause.

The stop in fighting is also intended to allow a significant increase in the amount of humanitarian assistance, including fuel, to enter the besieged enclave from Egypt.

“We’ve made some progress recently and have been working hard to advance this, but it remains a volatile situation,” an administration official said Saturday on condition of anonymity. After this article was initially published, National Security Council spokesperson Adrienne Watson tweeted that there was “no deal yet but we continue to work hard to get a deal.”

The outline of a deal was put together during weeks of talks in Doha, Qatar, among Israel, the United States and Hamas, indirectly represented by Qatari mediators, according to Arab and other diplomats. But it remained unclear until now that Israel would agree to temporarily pause its offensive in Gaza, provided the conditions were right.

A spokesperson for the Israeli Embassy in Washington said late Saturday that “we are not going to comment” on any aspect of the hostage situation.

Concern about the captives — two of whom Israel said were found dead — along with the rising number of Palestinian civilian casualties have steadily increased pressure on Prime Minister Benjamin Netanyahu’s government. More than 100 countries — but, notably, not the United States — have called for a full and immediate cease-fire.

The decision to accept the deal is difficult for Israel, said one person familiar with the situation who, like others, spoke on the condition of anonymity to discuss sensitive negotiations. While there is strong domestic pressure on Netanyahu to bring the hostages home, there are also loud voices in Israel demanding that the government not barter for their release.

In public remarks, Israel has remained unyielding, while acknowledging the pressure it is under. On Friday, Israeli National Security Council head Tzachi Hanegbi told reporters that the war cabinet had unanimously agreed that a limited cease-fire could occur only after “a massive release of our hostages … and it will be limited and short, because after that we will continue to work towards achieving our war goals.”

In fiery comments Saturday, Netanyahu said the offensive would continue, even as he defended a decision last week to allow the first steady fuel transfers into Gaza since the start of the war. As Israel has pursued its Gaza offensive, it has cut off all but minimal deliveries of the food, water, fuel and medicine that the enclave’s 2.3 million people depend upon for survival. “For international support to continue, humanitarian aid is essential,” he said. “Because of that, we accepted the recommendation to bring fuel into Gaza.”

Netanyahu spoke as thousands of hostage family members and their supporters ended a five-day march from Tel Aviv to Jerusalem to demand government action, with many saying that the lives of innocent Israeliswere worth any short-term deal the government has to make to secure their release.

under its own domestic pressure between advocates of unstinting support for Israel’s war aims and concern over the humanitarian crisis in Gaza, has fully backed a temporary pause in the fighting.

Beginning withPresident Biden’s trip to Tel Aviv a week after the war began, and followed by multiple visits from Secretary of State Antony Blinken and other senior officials, the administration has pushed hard with Netanyahuto understand that it is losing the narrative high ground as more Palestinians die. The death toll in Gaza is now reportedly more than 11,000.

The administration’s highest priority, however, has been freeing the nine Americans and one permanent U.S. resident among the hostages. “I think we need a pause,” Biden said two weeks ago at a campaign event. “A pause means time to get the prisoners out.”

A week later, asked about reports he had pushed for a three-day stop in the fighting, Biden said he had asked Netanyahu for “an even longer pause.” In his news conference Thursday after meeting with Chinese President Xi Jinping, he said that the hostages were “on our mind every single day,” and that he was working on a way to “have a period of time where there’s a pause long enough” to let them be released.

U.S. officials have said they believe a pause would allow Hamas to gather the hostages and arrangements could be made to escort them safely through the battlefield. It was not clear that the Americans or other foreigners would be included in the initial tranche of releases. The hope is that if the release of women and children is successful, other groups of captives will then follow.

Brett McGurk, the White House National Security Council’s top Middle East official, is on an extended trip to the region to try to solidify the hostage release plan, including meetings in Israel and Qatar. Speaking at an international security conference Saturday in Bahrain, McGurk said that negotiations have been “intensive and ongoing.”

The freeing several weeks ago of an American mother and daughter — among the four captives who have been released since the war began — during a brief pause to allow international humanitarian workers to escort them, provided a “track” for “what we hope will be a much larger release.”

McGurk told the conference that Hamas’s release of a “large number” of the hostages, believed to total 239, “would result in a significant pause in fighting and a massive surge of humanitarian relief. Hundreds and hundreds of trucks on a sustained basis entering Gaza from Egypt.” When the hostages are released, he said, “you will see a significant, significant change.

It was “reasonable,” McGurk said, “to pause the fighting, release the hostages, the women, the children, the toddlers, the babies, all of them.” The initial deal does not include civilian men or Israeli military personnel, a number of whom are women, among the captives.

Those remarks drew an angry response from Jordanian Foreign Minister Ayman Safadi, who interpreted them as signaling that a pause allowing humanitarian relief would come only after the hostages were released unconditionally by Hamas. “There’s a lot of negotiations,” Safadi said, “but Israel is taking 2.3 million Palestinians hostage … and denying them food and water and by this war.”

An administration official said any assumption that the United States was conditioning aid on the release of hostages had “grossly misinterpreted” McGurk’s remarks. “Any type of hostage deal would likely result in an increase of humanitarian aid,” the official said. The United States, the official noted, has continuously pushed for an increase of humanitarian assistance to civilians in Gaza.