It would allow hundreds of thousands of people displaced in Gaza to return to what remains of their homes and flood badly needed humanitarian aid into a devastated territory.
Three officials from the US and one from Hamas confirmed that a deal had been reached, while a senior Israeli official said details were still being ironed out.
All three US officials requested anonymity to discuss the contours of the deal before the official announcement by mediators in Doha.
US President Joe Biden was preparing to address the breakthrough agreement later on Thursday, officials said.
Any agreement still needs to be approved by Israeli Prime Minister Benjamin Netanyahu’s cabinet, but is expected to go into effect in the coming days.
The deal 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 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.
Still, the announcement offered the first sign of hope in months that Israel and Hamas may be winding down the most deadly and destructive war they’ve ever fought, a conflict that has destabilised the broader Middle East and sparked worldwide protests.
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.
Trump celebrated the soon-to-be-announced agreement in a posting on his Truth Social social media platform.
“We have a deal for the hostages in the Middle East. They will be released shortly. Thank you!” he posted, in all capitals.
Hamas triggered the war with its October 7, 2023, cross-border attack, which killed some 1200 Israelis and took 250 others hostage.
Israel responded with a fierce offensive that has killed more than 46,000 Palestinians, according to local health officials, displaced an estimated 90 per cent of Gaza’s population and sparked a humanitarian crisis.
More than 100 hostages were freed from Gaza in a week-long truce in November 2023.
U.N. and international relief organisations estimate that some 90 per cent 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 under way 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.
Radwan, who has been displaced from the town of Beit Lahiya for over a year and shelters in Gaza City, said he will try to return to his hometown, and “rebuild my house, and rebuild Beit Lahiya”.
He spoke to AP over the phone. His voice has been overshadowed by celebrations.
“People are crying here. They don’t believe it’s true,” he said.