More than 100 immigrant, refugee, human rights and humanitarian organizations sent a letter Monday demanding Congress and President Joe Biden reinstate funding to the United Nations Relief and Works Agency.

The letter, first seen by HuffPost, was addressed to President Biden, House Speaker Mike Johnson (R-La.) and Senate Majority Leader Chuck Schumer (D-N.Y.) a week after Congress passed a foreign aid package that finalized the Biden administration’s suspension of U.S. funding for the UNRWA, which was providing critical support in Gaza.

For more than 75 years, the relief agency has offered direct relief to nearly 6 million Palestinians in Gaza, the West Bank and neighboring Arab states. In Gaza, nearly the entire population relies on the aid group for basic necessities, including food, water and hygiene supplies, as other aid organizations suspended services after being targeted and killed by Israeli bombs that have rained on Gaza since October.

In February, Israeli officials made an explosive allegation: that a number of UNRWA employees in Gaza took part in the Oct. 7 Hamas attack that killed roughly 1200 people and saw 250 taken hostage.

But last week, an independent United Nations report concluded that Israeli forces did not provide evidence to support that accusation. Despite this, the backlash against UNRWA was swift. More than a dozen international donors, including the U.S., suspended about $450 million of aid. U.S. financial support for the relief agency is suspended until at least March 2025.

Germany, UNRWA’s second-biggest donor after the U.S., however, recently announced that it would resume funding for the aid group.

“Cutting off funding to UNRWA completely erodes the international community’s ability to respond to one of the worst humanitarian crises of our time,” the letter said. “International NGOs and other UN organizations have repeatedly stated that they do not have the personnel, resources, or infrastructure to respond to the humanitarian needs in Gaza appropriately.”

The Senate voted overwhelmingly to approve the foreign aid package last Tuesday night in a 79-18 vote after a monthslong delay. It includes billions of dollars slotted for Ukraine and Israel, as well as humanitarian aid for civilians in Gaza and the Indo-Pacific region.

“Prohibiting aid for an organization that could provide life-saving food, medicine and shelter for more than 2 million people is horrific, and it’s part of a pattern of policymaking that’s often rooted in racism and Islamophobia,” said Sunil Varghese, the policy director at the International Refugee Assistance Project, one of the letter’s signatories.

“It’s a matter of fact that no one can provide the kind of necessary assistance that UNRWA can,” Varghese added.

UNRWA chief Philippe Lazzarini said last week that the aid group currently has enough funding to pay for operations until June. But it is likely not enough, with reports of famine and starvation spreading across Gaza. At least 32 people, including 28 children, have died of starvation in Gaza since the Israeli government began using starvation as a war tactic.

Yumna Rizvi, the senior policy analyst at the Center for Victims of Torture, a nonprofit organization, told HuffPost that UNRWA’s services are critical for short-term needs and treating the long-term mental health impact of the war on Palestinians.

“What people are experiencing is not post-traumatic, in any sense of the term. This is an ongoing and continuous traumatic threat because it is not ending, and the survival skills that they’re using to stay alive, the longer they use them, the longer the detrimental impact it will have on their bodies,” Rizvi said.

“We’re going to see the impact of this for a lifetime, and it’s going to be incredibly detrimental to see how we just chose to turn our backs against this population,” she added.

The letter’s signatories, which include the National Immigrant Justice Center, Human Rights Watch and Palestine Legal, warned of “grave consequences” if the administration does not reverse course immediately.

“The United States should uphold its commitment to the human rights of the Palestinian people and resume its role as a strong supporter of UNRWA by passing legislation to reinstate funding to the humanitarian agency immediately,” the letter stated. “Failing to do so would be a moral stain on this Administration and Congress’s legacy.”