Israel and Hamas's negotiations continued overnight, with Israeli officials signaling that a release of hostages from Gaza and pause in fighting would be delayed.
The four-day halt in military operations in Gaza and freeing of hostages were initially envisaged to begin on Thursday morning.
The head of Israel's National Security Council said the releases would begin "not before Friday," underscoring the fragility of the complex accord with Hamas, which was announced earlier this week.
In northern Gaza, there were more battles between Hamas militants and Israeli troops on Wednesday night.
Qatar, which along with Egypt is acting as a mediator, said Thursday the timing of the truce's implementation would be announced "within the coming hours."
US President Joe Biden spoke with key players, including Israeli Prime Minister Benjamin Netanyahu and the leaders of Qatar and Egypt. The White House emphasized the need for all parts of the deal to be executed.
Israel and Hamas agreed that the Iran-backed group would free 50 women and children held in Gaza. In turn, Israel will release 150 women and Palestinians under the age of 19 from Israeli jails. US officials said three Americans would be among the hostages leaving Gaza.
Netanyahu said the war will carry on until Hamas is destroyed as an organization, but the accord will still mark the first major lull in fighting since the conflict erupted just over six weeks ago.
Israeli media have reported that the cease-fire would start only after the Red Cross receives hostages from Hamas, designated a terrorist group by the US and the European Union.
"Negotiations on the release of our hostages are progressing and continuing all the time," Tzachi Hanegbi, head of Israel's National Security Council, said.
Under the deal, more aid is expected to flow into Hamas-controlled Gaza to alleviate what the United Nations and Palestinian officials say is a humanitarian disaster. A second stage could see the pause in fighting extended another day for every 10 additional hostages released.
The agreement falls short of calls from many nations for an extended cease-fire. Israel and the US have rejected such a move, saying it would allow Hamas to rearm.
The deal's outcome has high stakes for Biden, who faces pressure from many in his own party to bring an end to Israel's offensive, launched after an Oct. 7 Hamas attack that killed 1,200 people and saw 240 taken hostage. More than 14,500 people, including 6,000 children, have since been killed in the Palestinian enclave, according to the Hamas-run health ministry.
Qatar said the "humanitarian pause" could help stop the war and lead to a "just peace process."
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Netanyahu, though, has made clear Israel won't let up.
"We are committed to destroying Hamas, getting all of our hostages back and making sure Gaza is no longer a threat to Israel," he said.
He's also instructed Mossad, Israel's foreign-intelligence agency, "to act against the leaders of Hamas wherever they are." Defense Minister Yoav Gallant said Hamas's leaders were "living on borrowed time," and the fight against them would "span the entire globe."
Diplomatic efforts to contain the conflict continued. An Arab delegation headed by Saudi Arabia's top diplomat, Prince Faisal bin Farhan, visited London on Wednesday, before heading to Paris for talks with French President Emmanuel Macron. UK Foreign Secretary David Cameron arrived in Israel on Thursday and is due to meet Israeli and Palestinian officials, Sky News reported.
Iran Top Diplomat Meets Hamas, Islamic Jihad Officials in Beirut
Events elsewhere in the region over the past 24 hours have underlined the risks of spillover.
To Israel's north in Lebanon, an Israeli airstrike on a house in the village of Beit Yahoun killed four people and wounded another, according to Lebanese state media.
Lebanese militant group Hezbollah, which has launched regular rocket attacks on Israel, said five of its members were killed, including the son of the head of its bloc in parliament, according to Al Manar TV. It didn't give details and it wasn't clear if it was the same incident.
The US said Wednesday that one of its destroyer ships in the Red Sea shot down several drones launched from Yemen. The country's Iran-backed Houthi rebels have pledged to keep targeting Israel until its ends the war.
It's not clear if groups such as Hezbollah and the Houthis will also adhere to the truce between Hamas and Israel.
Jordan's Foreign Minister Ayman Safadi warned the longer Israel presses ahead with its assault on Gaza, the greater the risk of a wider conflict and terrorist attacks on Western assets.
There is a concern that "if we get to a certain point there's no going back," he said.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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