Losing significant funding from its largest donor, the United States, could be "catastrophic" for Palestinians, said a UN agency that provides aid to Palestinian refugees.
Last week, President Donald Trump said the United States may withhold future aid payments to the UN Relief and Works Agency (UNRWA) over what he called the Palestinians' unwillingness to talk peace with Israel.
A State Department official later said that no decision had been made on payment.
The United States is the largest donor to the agency, with a pledge of nearly $370 million as of 2016, according to UNRWA's website.
The UN agency, founded in 1949 to aid Palestinian refugees, provides educational and health services in the Gaza Strip and the West Bank.
"The human impact of losing significant funding could be catastrophic in the real lives of real people whom the UN is mandated to protect,"
UNRWA spokesman Chris Gunness told the Thomson Reuters Foundation in a statement.
"Palestine refugees are among some of the most vulnerable people in the Middle East. Our health services offer a life line, quite literally, to vulnerable women and children, the sick and the elderly," he said.