Israeli Prime Minister Benjamin Netanyahu is warning that a ceasefire cannot go forward on Sunday unless Israel receives the list of names of hostages to be released from Gaza as agreed.
Israel had expected to receive the names by 4pm local time – 2pm GMT – on Saturday.
Mr Netanyahu said in a statement that “Israel will not tolerate violations of the agreement”.
Hamas was to give the names to mediator Qatar. There is no immediate response to questions from Qatar or Hamas.
The ceasefire between Hamas and Israel is to go into effect in less than 24 hours, Qatar’s foreign ministry had said.
In a post on X, Qatar’s foreign minister Majid al-Ansari said the ceasefire would go into effect at 8.30am (0630 GMT) on Sunday.
Early on Saturday morning, Israel’s Cabinet approved the deal for a ceasefire in Gaza that would release dozens of hostages and pause the 15-month war with Hamas, bringing the sides a step closer to ending their deadliest and most destructive fighting ever.
Under the deal, 33 hostages are set to be released over the next six weeks, in exchange for hundreds of Palestinians imprisoned by Israel.
The remainder, including male soldiers, are to be released in a second phase that will be negotiated during the first. Hamas has said it will not release the remaining captives without a lasting ceasefire and a full Israeli withdrawal.
Key questions remain about the ceasefire, however, the second achieved during the war, including the names of the 33 hostages who are to be released during the first, six-week phase and who among them is still alive.
Hamas has agreed to free three female hostages on day one of the deal, four on day seven and the remaining 26 over the following five weeks.
Palestinian detainees are to be released as well.
Israel’s justice ministry published a list of more than 700 who are to be freed in the deal’s first phase and said the release will not begin before 4pm local time on Sunday.
All people on the list are younger or female.
The largely devastated Gaza should see a surge in humanitarian aid. Trucks carrying aid lined up Friday on the Egyptian side of the Rafah border crossing into Gaza.
Hamas triggered the war with its October 7 2023, cross-border attack into Israel that killed some 1,200 people and left some 250 others captive.
Nearly 100 hostages remain in Gaza.
Israel responded with a devastating offensive that has killed more than 46,000 Palestinians, according to local health officials, who do not distinguish between civilians and militants but say women and children make up more than half the dead.
UN Secretary-General Antonio Guterres said the distribution of humanitarian aid in Gaza once the ceasefire takes effect will face many obstacles.
He said there are limited number of trucks at the present in Gaza “so a lot of actions are necessary in order to make the distribution fully effective”.
He said the ceasefire makes it clear that there would not be any impediments by Israel for humanitarian aid to enter Gaza.
Mr Guterres said the distribution will be carried out by the UN and its partners as well as the private sector and other initiatives.
“It is clear that there is an obligation by Israel of not creating any obstacles,” Mr Guterres said.
He added: “It is clear that the situation in Gaza is still extremely complex and a lot of difficulties still remain for an effective distribution.”
