CAIRO/TEL AVIV - Hamas said on Monday it would next release hostages held in Gaza on Saturday, after an official with the Palestinian militant group had said they would be released a day later than expected.

Hamas is set to release more than 90 hostages over the coming weeks as part of a complex ceasefire deal reached with Israel this month that could end the 15-month war in Gaza.

The militant group said in a statement that the next group of hostages would be released on Saturday in exchange for Palestinian prisoners and detainees who are held by Israel.

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Earlier, Nahed Al-Fakhouri, head of the Hamas prisoners' media office, had said the hostages would be released on Sunday. Hamas had been expected to release four Israeli hostages on Saturday, seven days after the ceasefire came into effect.

A senior Israeli official, speaking on the condition of anonymity, reacted to Al-Fakhouri's statement by telling Reuters the deadline for the hostages to be released was Saturday.

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This month, Israel and Hamas agreed to a three-phase ceasefire that could bring an end to the 15-month war in Gaza. The ceasefire came into effect on Sunday with Hamas releasing three Israeli hostages. Israel also released Palestinian prisoners and detainees.

The ceasefire accord outlines a six-week initial ceasefire phase and includes the gradual withdrawal of Israeli forces from the Gaza Strip and the release of hostages taken by Hamas in exchange for Palestinian prisoners held by Israel.