CAIRO - Egypt has proposed an initial two-day ceasefire in Gaza to exchange four Israeli hostages of Hamas for some Palestinian prisoners, Egypt's president said on Sunday as Israeli military strikes killed 45 Palestinians across the enclave.

Egyptian leader Abdel Fattah al-Sisi made the announcement as efforts to defuse the devastating, more than year-long war resumed in Qatar with the directors of the CIA and Israel's Mossad intelligence agency taking part.

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Speaking alongside Algerian President Abdelmadjid Tebboune during a press conference in Cairo, Sisi also said that talks should resume within 10 days of implementing the temporary ceasefire in efforts to reach a permanent one.

There was no immediate comment from Israel or Hamas but a Palestinian official close to the mediation effort told Reuters: "I expect Hamas would listen to the new offers, but it remains determined that any agreement must end the war and get Israeli forces out of Gaza."

Israel has said the war cannot end until Hamas has been wiped out as a military force and governing entity in Gaza.

The US, Qatar and Egypt have been spearheading negotiations to end the war that erupted after Hamas fighters stormed into southern Israel on Oct 7 last year, killing 1,200 people and taking more than 250 hostages, by Israeli tallies.

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The death toll from Israel's retaliatory air and ground onslaught in Gaza is approaching 43,000, Gaza health officials say, with the densely populated enclave in ruins.

An official briefed on the talks told Reuters earlier on Sunday that negotiations in Doha will seek a short-term ceasefire and the release of some hostages being held by Hamas in exchange for Israel's release of Palestinian prisoners.

The objective, still elusive after multiple mediation attempts, is to get Israel and Hamas to agree to a halt in fighting for less than a month in the hope this would lead to a more permanent ceasefire.

At least 43 of those killed in Gaza on Sunday were in the north of the enclave, where Israeli troops have returned to root out Hamas fighters who it says have regrouped there.

'Unbearable' conditions in north Gaza

The United Nations said the plight of Palestinian civilians in northern Gaza was "unbearable" and the conflict was being "waged with little regard for the requirements of international humanitarian law".

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"The Secretary-General (Antonio Guterres) is shocked by the harrowing levels of death, injury and destruction in the north, with civilians trapped under rubble, the sick and wounded going without life-saving health care, and families lacking food and shelter, amid reports of families being separated and many people detained," UN spokesperson Stephane Dujarric said in a statement.

Israeli authorities were hampering efforts to deliver food, medicine and other essential humanitarian supplies, putting lives at risk, he said. The devastation and deprivation resulting from Israeli military operations in the north were making life there untenable.

Israel says its forces operate in accordance with international law. It says it targets Hamas operatives who conceal themselves among the civilian population which they use as human shields, a charge Hamas denies.

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It denies blocking humanitarian aid to Gaza, blaming international organizations for problems distributing it and accusing Hamas of stealing from aid convoys.

Jabalia in focus

Earlier on Sunday, 20 people were killed following an airstrike on houses in Jabalia, the largest of the Gaza Strip's eight historic refugee camps, which has been the focus of an Israeli military offensive for more than three weeks, medics and the Palestinian official news agency WAFA said.

Another Israeli airstrike on a school sheltering displaced Palestinian families in Shati camp in Gaza City, killed nine people and wounded 20 others, with many in critical condition, medics said.

Footage circulated on Palestinian media, which Reuters could not immediately verify, showed people rushing to the bomb site to help evacuate the casualties. Bodies were scattered on the ground, while some carried wounded children in their arms before loading them in a vehicle.

The Israeli military said it was looking into the report on the strike on the school.

Three local journalists were among those killed at the school in Shati - Saed Radwan, head of digital media at Hamas Al-Aqsa television, Hanin Baroud, and Hamza Abu Selmeya, according to Hamas media.

On Sunday, Israel's military said it had killed more than 40 militants in the Jabalia area in the past 24 hours, as well as dismantling infrastructure and locating large quantities of military equipment.

Israeli military strikes on the towns of Jabalia, Beit Hanoun and Beit Lahiya in northern Gaza have so far killed around 800 people during a three-week offensive, the Gaza health ministry said.