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The White House on Monday said it was reviewing Hamas's response to a proposed ceasefire and repeated that the US opposes Israel's plan to launch a major military operation in the southern Gazan city of Rafah.
“We are at a critical stage,” National Security spokesman John Kirby told reporters at the White House.
“We got a response from Hamas. We're currently reviewing that response and we're discussing it with our partners in the region.”
CIA director William Burns is in the region, Mr Kirby said, where he is assessing Hamas's announcement that it had accepted the terms of the ceasefire, which has been weeks in the making.
“We want to get these hostages out, we want to get a ceasefire in place for six weeks, we want to increase humanitarian assistance,” Mr Kirby said.
Earlier on Monday, US President Joe Biden spoke to Israeli Prime Minister Benjamin Netanyahu to reaffirm his position on Rafah.
Mr Biden has repeatedly said his administration opposes a major operation in Rafah, where more than one million Palestinians are sheltering in tents and overcrowded apartments after they were ordered to flee from other parts of the Gaza Strip.
“President Biden doesn't want to see operations in Rafah that put at greater risk more than a million innocent people who are seeking shelter,” Mr Kirby said, adding that the “constructive” phone call lasted about 30 minutes.
Israel's military on Monday ordered 100,000 Palestinians in Rafah to evacuate, indicating a ground invasion could be imminent.
Mr Netanyahu has for weeks been threatening to launch a major offensive on Rafah, saying it was necessary to root out Hamas, the militant group that led the October 7 attack on Israel that killed about 1,200 people, according to Israeli tallies.
In response, Israel's attack on Gaza has killed more than 34,600 Palestinians, mostly women and children, local health authorities say.
Last week, Israel briefed Biden administration officials on a plan to evacuate Palestinians civilians before any military operation in Rafah, AP reported, quoting US officials.
But the Israeli plan did not change the US administration's view on going ahead with an operation in Rafah.
The Biden administration has frequently said it would not back an Israeli operation in Rafah without a “credible” plan that would ensure the safety of the 1.5 million Palestinians sheltering there.
Any plan should also ensure the civilians have access to shelter, food and sanitation, US officials have said.
Mr Netanyahu agreed in Monday's call to ensure that Karam Abu Salem crossing – the border entry between Gaza, Israel and Egypt – would remain open for the entry of humanitarian assistance.
The call came before Mr Biden hosted Jordan's King Abdullah II for a private lunch at the White House.
UN spokesman Stephane Dujarric condemned Israel's order for Palestinians to evacuate from Rafah as “impossible to carry out safely”, and pushed for Israel to agree to a ceasefire.
Secretary General Antonio Guterres “reiterates his pressing call to both the government of Israel and the leadership of Hamas to go the extra mile needed to make an agreement come true and stop the present suffering", Mr Dujarric said.
“The Secretary General reminds the parties that the protection of civilians is paramount in international humanitarian law.
Meanwhile, the UN High Commissioner for Human Rights, Volker Turk, on Monday warned civilian deaths, suffering and destruction were set to increase beyond already unbearable levels in Rafah.
“Gazans continue to be hit with bombs, disease and even famine. And today, they have been told they must relocate yet again as Israeli military operations into Rafah scale up.”
Adla Massoud contributed to this report from the UN
