As US President Donald Trump pulls back funding for the United Nations agency for Palestinian refugees, UNRWA, Palestinians in Syria are facing "life-threatening" conditions, the agency's spokesperson said.
"Palestinians are among those worst affected by the [Syrian] conflict," said UNRWA spokesperson Chris Gunness, explaining that 95 percent of 438,000 Palestinians in the war-torn country are "in critical need of sustained humanitarian assistance".
"The war in Syria has devastated lives with incalculable cruelty. In this situation, many of the services UNRWA provides are often literally life-saving," Gunness told Al Jazeera, referring to UNRWA's makeshift clinics, emergency assistance and teaching staff that educates 45,000 students a day.
Nearly 58 percent of Palestinians in Syria are internally displaced, with upwards of 56,600 trapped in hard-to-reach or inaccessible parts of the war-ravaged country, he added.
Earlier this month, the Trump administration announced that the US will indefinitely withhold $65m of its planned $125m in financial contributions to UNRWA, prompting outrage from Palestinians and humanitarian groups.
Salim Salamah, director of the Palestinian League for Human Rights - Syria, argued that Palestinian refugees in Syria and those who have been doubly displaced to neighbouring countries will suffer as a result of the decision.
"The impact is going to be really massive and tragic," he told Al Jazeera.
"For Palestinians of Syria, it's life-saving aid, especially in the context that many Palestinians lack access to many basic services, even [those who fled] in Lebanon or Jordan."
Salamah added: "It falls within the long-standing tradition of eroding the existence of Palestinians ... and it is tragic."
'At stake is dignity'
Earlier this month, US Department of State spokeswoman Heather Nauert said the decision was not "aimed at punishing anyone".
Responding at the time, UNRWA Commissioner-General Pierre Krahenbuhl said: "At stake is the dignity and human security of millions of Palestine refugees, in need of emergency food assistance and other support."
The move came just weeks after Trump took to Twitter to accuse the Palestinians of showing "no appreciation or respect" for hundreds of millions of dollars in US aid each year.
On Thursday, 21 aid groups warned of "dire consequences" in an open letter to US Ambassador to the UN Nikki Haley, Secretary of State Rex Tillerson, National Security Advisor HR McMaster, and Secretary of Defence James Mattis.
"We are deeply concerned by the humanitarian consequences of this decision on life-sustaining assistance to children, women and men in Jordan, Lebanon, Syria and the West Bank and Gaza Strip," it said.
Millions of Palestinian refugees, including those uprooted from their homes during Israel's 1948 establishment and their descendants, are spread across the map of the Middle East and elsewhere.
'Basic livelihood becoming a bargaining chip'
More than half-a-million Palestinians lived in refugee camps, cities and towns across Syria before the war started.
At least 125,000 of the prewar population have since fled Syria and landed in Jordan, Lebanon, Turkey, Europe and elsewhere, according to UNRWA.
Residents of many Palestinian camps, such as the Damascus-area Yarmouk camp, have suffered from air raids, shelling, siege, malnutrition, displacement and widespread destruction owing to fighting between government forces and armed groups.
On Wednesday, the Action Group for Palestinians of Syria watchdog announced that the total number of Palestinians killed in Yarmouk camp since the conflict started has reached 1,335.
Across the country, upwards of 3,642 Palestinians have died during the nearly seven years of war, while another 1,651 are believed to be detained and more than 300 are still unaccounted for, the group said.
Referring to the Trump administration's decision to pull back UNRWA funding, Salamah said: "I don't know what is expected from us beyond accepting the horror of war, displacement and the lack of international protection."
He concluded: "Even our very basic livelihood is becoming a bargaining chip."