The head of the CIA and Israel's top spy chief traveled to Doha on Tuesday in the latest push for a Gaza ceasefire deal, sources said.

CIA director William Burns and Mossad director David Barnea arrived in the Qatari capital as part of the effort by mediators from the US, Egypt and Qatar to secure a truce between Israel and Hamas after nine months of war.

They are due to meet Qatari Prime Minister Mohammed bin Abdulrahman Al Thani and have indirect talks with Hamas leaders.

 Burns flew to Doha from Cairo, while Barnea, making his second trip to Qatar in less than a week, travelled from Israel.

Their trip to Qatar follows a series of meetings late on Monday in Cairo in which mediators and Israeli officials tried to close the gap between the warring parties over US ceasefire proposals unveiled in May.

Beside Burns, US Middle East envoy Brett McGurk took part in the Cairo talks.

 Burns and Egypt's President Abdel Fattah El Sisi also met on Tuesday and discussed the efforts to reach a ceasefire, according to  El Sisi’s media office.

'Intense' discussions over Rafah

In parallel to the ceasefire negotiations, Israel outlined to Egypt its conditions for withdrawing from the Gaza side of the Rafah crossing and the border corridor between Egypt and Gaza.

The sources said Israel’s domestic security chief, Shin Bet’s Ronen Bar, had lengthy and “sometimes intense” discussions with Egyptian and US officials on the topic in Cairo on Monday.

Israeli forces captured the border crossing and the 13km border corridor, known as the Philadelphi corridor, in May. The move angered Egypt's government, which responded by closing the crossing.

Since then, desperately needed humanitarian assistance has been unable to reach Palestinians via Rafah.

“It was nothing like people meeting over tea and cakes and having a friendly discussion,” said one source.

“It was intense and the discussion was heated at times.”

Israel is prepared to pull out its troops from the Gaza side of the Rafah crossing on the condition that it first installs security cameras and sensors to monitor traffic, the sources said.

It also wants the facility to be run by an international force with Israel retaining a superior security role.

Israel also wants a six-metre-high wall to be built in phases along the length of the Philadelphi corridor and to retain the right to send troops back to the area when it deems necessary.

Israel claims that weapons, money and personnel were being smuggled from Egypt to Gaza through a network of underground tunnels before reaching Hamas. Egypt has strongly denied the accusations.

Ceasefire gaps remain

The US, Qatar and Egypt have been trying for months without success to broker a deal to end the Gaza war, now in its 10th month, and get Hamas and Israel to agree to a prisoner and hostage swap.

More than 38,200 Palestinians have been killed in Gaza since October, when Hamas launched an attack on southern Israel that killed about 1,200 people.

The war has displaced more than 80 per cent of the coastal enclave’s 2.3 million residents and reduced most of its built-up areas to rubble. It has also created a humanitarian crisis, with many people facing hunger and famine looming over the northern part of Gaza.

Despite mounting international unity over the need for a ceasefire, several attempts at securing one have failed following the collapse of a one-week truce in November.

The flurry of intense diplomacy in Cairo and Doha has followed a softening by Hamas of its conditions to accept the US proposals announced by President Joe Biden on May 31.

Israel, however, appears not to have budged on its previously declared positions, including its unwillingness to fully withdraw from Gaza and its insistence on retaining a commanding security role in postwar Gaza.

Israel's Prime Minister Benjamin Netanyahu has repeatedly vowed he would not accept a permanent ceasefire and will continue fighting until Hamas is destroyed.

Speaking at a briefing in Washington on Monday, White House national security spokesman John Kirby said gaps remained between Israel and Hamas.

“We've been working this very, very hard. And there are still some gaps that remain in the two sides in the positions, but we wouldn't have sent a team over there if we didn't think that we had a shot here,” Kirby said.

“We're trying to close those gaps as best we can,” he added.

Hamas has raised hopes that a deal could soon be struck when it dropped its previous demand that it would not sign a deal unless Israel first agreed in writing to a permanent ceasefire.

The Palestinian group now says it wants guarantees by the mediators that talks on reaching a permanent ceasefire begin as soon as the initial 42-day truce prescribed by the proposals takes hold.

It also said it would accept the release of Palestinians held in Israeli prisons in exchange for the freedom of hostages it is holding to be staggered over the three phases of the US proposals.

However, Hamas has demanded that detainees of its choosing are released, including high-profile figures such as Marwan Barghouti, a senior figure from the mainstream Palestinian Fatah faction who is seen widely as a possible successor to Palestinian President Mahmoud Abbas.

Israel has yet to formally respond to the latest Hamas positions, but the sources said its conditions have been informally relayed to the mediators. These conditions, they said, roughly mirror Netanyahu’s often repeated rejection of a permanent ceasefire and commitment to destroying Hamas.

On Monday, a Palestinian official with knowledge of the talks told AFP that while a Hamas delegation would take part in indirect talks with Israel, there were several “points of divergence” between the two sides.

Among them, he said, was the Israeli refusal to release 100 Palestinian prisoners who received heavy sentences and “have spent more than 15 years in Israeli prisons, including senior leaders from Hamas, Fatah, [Palestinian Islamic] Jihad and the Popular Front”.

Hamas political chief Ismail Haniyeh, who is based in Qatar, also said on Monday that Israel's military actions in Gaza could push the ceasefire talks back to square one.

The group said on its Telegram channel that Haniyeh, in a call to mediators, said he holds Netanyahu fully responsible for the potential collapse of negotiations.