By Robert Plummer, BBC News
More countries have halted funding to the largest UN agency operating in Gaza, as the crisis deepens over the alleged role of some staff in the 7 October Hamas attacks on Israel.
Japan and Austria said they were suspending payments to the UN agency for Palestinian refugees, UNRWA.
The US, UK, Germany and Italy are also among those who have suspended funding.
UNRWA has told the BBC it is "extremely desperate" and that "the humanitarian needs in Gaza are growing by the hour".
The agency has sacked several of its staff over allegations they were involved on 7 October, when Hamas gunmen infiltrated Israel, killing about 1300 people - mainly civilians - and taking about 250 others back to Gaza as hostages.
More than 26,000 people - mostly women and children - have been killed in Gaza since Israel launched a major military operation in response, the territory's Hamas-run health ministry says. Another 1.7 million people have fled their homes, with many of them sheltering at UNRWA facilities.
According to a report in the New York Times, an Israeli intelligence dossier alleges that nearly 200 UNRWA workers are Hamas or Islamic Jihad operatives, without providing detailed evidence.
The dossier also alleges that at least 12 workers crossed into Israel on 7 October. UNRWA has sacked nine of those employees and says it is investigating.
Another report published by the Wall Street Journal, also citing the Israeli intelligence dossier, alleges that about 1200 of UNRWA's 12,000 employees in Gaza have links to Hamas or Islamic Jihad. The UN has declined to comment, saying an internal investigation into the agency is under way.
But earlier on Sunday UN Secretary-General Antonio Guterres said he was "horrified" by the accusations relating to the 7 October attack. Despite that, he has appealed to donor countries to "guarantee the continuity of UNRWA's operations".
In a statement on Sunday, he said: "Of the 12 people implicated, nine were immediately identified and terminated by the Commissioner-General of UNRWA, Philippe Lazzarini; one is confirmed dead and the identity of the two others is being clarified."
He said Gaza should not be penalised for the allegations.
On Monday, Israeli Foreign Minister Israel Katz said he had cancelled meetings with Lazzarini and called on him to resign.
An UNRWA spokesperson said that if funding was not resumed, the agency would not be able to continue its operations beyond the end of February.
Announcing its decision to suspend payment, Japan's foreign ministry said late on Sunday that it was "extremely concerned about the alleged involvement of UNRWA staff members in the terror attack on Israel".
It added that it had been "strongly urging" UNRWA to investigate the allegations "in a prompt and complete manner".
Japan is the sixth-largest donor to the agency, according to UNRWA's 2022 figures.
On Monday, Austria said it was following suit, calling for "a comprehensive, swift and complete investigation into the allegations".
Juliette Touma, the director of communications at UNRWA, said in a BBC interview that the allegations were "extremely serious" and that Lazzarini had taken an "extraordinary measure" in immediately dismissing the staff members in question.
"We are extremely desperate. It has come at a time when the humanitarian needs in Gaza are growing by the hour," she said, adding that she had visited the territory herself last week.
"People continue to be displaced. People are hungry. The clock is ticking fast towards famine.
"We are doing everything possible to avert us from getting towards famine. But this lack of funding that we have been faced with now, when at least 10 of the largest donors have put a temporary pause on the funding, this is going to have very, very serious repercussions on what is, right now, the largest humanitarian operation in Gaza."
She said UNRWA had not seen the evidence, but the allegations were being investigated by the UN's oversight office in New York.
On Friday, an adviser to the Israeli prime minister told the BBC that the 7 October Hamas attacks had involved "people who are on their [UNRWA] salaries".
Mark Regev said there was also information showing teachers working in UNRWA schools had "openly celebrated" the 7 October attacks.
This story was originally published by the BBC.