DOHA, Qatar — Israel and Hamas agreed to a ceasefire deal to pause the devastating war in the Gaza Strip, multiple officials announced Wednesday, raising the possibility of winding down the deadliest and most destructive fighting between the bitter enemies.

The deal promises the release of dozens of hostages held by Hamas in phases and hundreds of Palestinian prisoners in Israel, and it will allow hundreds of thousands of people displaced in Gaza to return to what remains of their homes. It also would flood badly needed humanitarian aid into a territory ravaged by 15 months of war.

The prime minister of Qatar, Sheikh Mohammed bin Abdulrahman Al Thani, said the ceasefire would go into effect on Sunday. He made the announcement in the Qatari capital of Doha, the site of weeks of painstaking negotiations.

U.S. President Joe Biden touted the deal from Washington, saying the ceasefire will stay in place as long as Israel and Hamas remain at the negotiating table over a long-term truce. Biden said his administration and President-elect Donald Trump's team were "speaking as one" in the negotiations.

The office of Israeli Prime Minister Benjamin Netanyahu said final details were being ironed out, saying in a statement that it hoped "details will be finalized tonight."

An Israeli official familiar with the talks who spoke on condition of anonymity said those details center on confirming the list of Palestinian prisoners who are to be freed. Any agreement must be approved by Netanyahu's Cabinet.

Once the deal begins, it is expected to deliver an initial six-week halt to fighting that is to be accompanied by the opening of negotiations on ending the war altogether.

Over those six weeks, 33 of the nearly 100 hostages are to be reunited with their loved ones after months in in captivity with no contact with the outside world, though it's unclear if all are alive.

It remained unclear exactly when and how many displaced Palestinians would be able to return to what remains of their homes and whether the agreement would lead to a complete end to the war and the full withdrawal of Israeli troops from Gaza — key Hamas demands for releasing the remaining captives.

Many longer-term questions about postwar Gaza remain, including who will rule the territory or oversee the daunting task of reconstruction after a brutal conflict that has destabilized the broader Middle East and sparked worldwide protests.

Hamas triggered the war with its Oct. 7, 2023, cross-border attack, which killed some 1,200 Israelis and took 250 others hostage. Israel responded with a fierce offensive that has killed over 46,000 Palestinians, according to local health officials, displaced an estimated 90% of Gaza's population and sparked a humanitarian crisis.

More than 100 hostages were freed from Gaza in a weeklong truce in November 2023.

The U.S., along with Egypt and Qatar, have brokered months of indirect talks between the bitter enemies that finally culminated in this latest deal. It comes after Israel and the Lebanese militant group Hezbollah agreed to a ceasefire in November, after more than a year of conflict linked to the war in the Gaza.

Israel responded with a brutal air and ground offensive that has killed over 46,000 Palestinians, according to local health officials. They do not distinguish between civilians and militants but say women and children make up more than half of those killed.

U.N. and international relief organizations estimate that some 90% of Gaza's 2.3 million people have been displaced, often multiple times. They say tens of thousands of homes have been destroyed and hospitals are barely functioning. Experts have warned that famine may be underway in northern Gaza, where Israel launched a major offensive in early October, displacing tens of thousands of residents.

"The best day in my life and the life of the Gaza people," Abed Radwan, a Palestinian father of three, said of the ceasefire deal. "Thank God. Thank God."

Radwan, who has been displaced from the town of Beit Lahiya for over a year and shelters in Gaza City, said he hopes to return and to rebuild his home. As he spoke to AP by phone, his voice was overshadowed by the celebrations of fellow Gazans.

"People are crying here. They don't believe it's true," he said.

In Israel, hundreds of demonstrators gathered outside Israel's military headquarters in Tel Aviv, calling for a deal to be completed. Many held posters of hostages held by Hamas, others hoisted candles in the air.

As the deal was announced, some people were unaware that it had gone through. Sharone Lifschitz, whose father Oded is being held in Gaza, told the AP by phone she was stunned and grateful but won't believe it until she sees all the hostages come home.

"I'm so desperate to see them if by some miracle my father has survived," she said.

Biden, who has provided crucial military aid to Israel but expressed exasperation over civilian deaths, announced the outline of the three-phase ceasefire agreement on May 31. The agreement eventually agreed to followed that framework.

He said the first phase would last for six weeks and include a "full and complete ceasefire," a withdrawal of Israeli forces from densely populated areas of Gaza and the release of a number of hostages, including women, older adults and wounded people, in exchange for the release of hundreds of Palestinian prisoners. Humanitarian assistance would surge, with hundreds of trucks entering Gaza each day.

The second and most difficult phase would include the release of all remaining living hostages, including male soldiers, and Israeli forces would withdraw from Gaza. The third phase calls for the start of a major reconstruction of Gaza, which faces decades of rebuilding from devastation caused by the war.

Hamas had been demanding assurances for a permanent end to the war and complete withdrawal of all Israeli forces from Gaza. Israel, meanwhile, has repeatedly said it would not halt the war until it destroys Hamas' military and governing capabilities.

The various players have conducted months of on-again, off-again negotiations. But with Biden's days in office numbered and President-elect Donald Trump set to take over, both sides had been under heavy pressure to agree to a deal.