The head of the U.N. agency that helps 5.3 million Palestinian refugees on Monday urged donors who filled a $446 million hole in its budget last year after the Trump administration drastically cut the U.S. contribution to be equally generous this year.

'Last year we had an extraordinary crisis and an out of the ordinary response,' Pierre Krahenbuhl said in an interview with The Associated Press. 'Our humble request to all the donors is: Please keep your funding levels at the same level as 2018.'

He said he has been thanking donors for their 'exceptional' contributions that enabled the U.N. Relief and Works Agency to fund its entire 2018 budget of $1.2 billion.

Krahenbuhl said the agency, known as UNRWA, also adopted a $1.2 billion budget for 2019, and this year it is getting nothing from the United States. Last year, the Trump administration gave $60 million, a dramatic reduction from the $360 million it provided in 2017, when the United States was the agency's largest donor.

U.S. President Donald Trump said in January 2018 that the Palestinians must return to peace talks to receive U.S. aid money a comment that raised alarm from leaders of 21 international humanitarian groups, who protested that the administration's link between aid and political objectives was 'dangerous.'

Krahenbuhl said the campaign that UNRWA launched immediately after the U.S. slashed its contribution succeeded as a result of 'very important donations,' starting with the European Union, which became the agency's biggest donor. He said 40 countries and institutions increased funding to UNRWA, including Germany, United Kingdom, Sweden, Japan, Canada and Australia. Qatar, Saudi Arabia, United Arab Emirates and Kuwait each gave $50 million, he said.

'Countries that supported us last year I would say were extremely proud to contribute to the solution,' Krahenbuhl said.

Last year, he said, the number of multi-year funding agreements with donors rose to 19.

So UNRWA right now is in 'a somewhat better position' than it was last year, with a shortfall of just over $200 million, Krahenbuhl said.

So far this year, the agency has received $245 million and is expecting $100 million more, he said, which means it should be financially OK until about May.

'But from then on we'll start to ... reach some crisis points,' Krahenbuhl said.

He said UNRWA is thinking about holding some events in the next two or three months 'to collectively mobilize the donor community.' In June, he said, there will be a pledging conference at which the U.N. and donors will take stock of the agency's financial situation.

Krahenbuhl said he is committed to making up for the $60 million that UNRWA is losing from the United States this year through internal cost saving measures to reduce the agency's expenditures.

'That's going to hurt, but that's where we feel our financial responsibility, so that we preserve the trust that was generated by the level of donors,' he said, noting that UNRWA last year saved $92 million.

Krahenbuhl said donors recognize the agency does important work. He pointed to the 280,000 boys and girls in UNRWA schools in Gaza and the food assistance the agency provides to 1 million people there every three months. 'That's half of Gaza's population,' he said.

The UNRWA chief also said that continuing the agency's services to Palestinian refugees in Syria, Lebanon, Jordan, Gaza and elsewhere in the Mideast 'is in everybody's interest' and important for stability in the region.

'If you take Gaza right now ... it's continuously at the razor's edge,' Krahenbuhl said, stressing that any shift in humanitarian assistance or conditions that people live in 'can trigger the need for justification, or the excuse ... to go back to war.'

Noting his own experience in the 2014 war between Israel and Hamas, which controls Gaza, Krahenbuhl said, 'this is absolutely devastating and needs to be avoided.'