U.N. Secretary-General Antonio Guterres said Friday that Washington has notified many U.N. agencies and humanitarian and development organizations this week of “severe” funding cuts, which he said will be “devastating” for the world’s most vulnerable people, and he urged the Trump administration to reconsider them.

“Going through with these cuts will make the world less healthy, less safe and less prosperous,” Guterres told reporters at the United Nations. “The reduction of America’s humanitarian role and influence will run counter to American interests globally.”

He urged the United States, as well as other countries that have recently announced reductions in humanitarian and development aid, to reverse their decisions after more careful reviews of the programs.

“In the meantime, every United Nations agency stands ready to provide the necessary information and justification for its projects,” Guterres added. “And we look forward to working with the United States in this regard.”

The U.N. chief did not give a dollar figure of how much the U.N. and its agencies will lose and would not take reporters’ questions. But the United States is the largest single donor in terms of humanitarian funding to the United Nations humanitarian appeal. In 2024, it provided $14 billion, just over 40% of the total contributions. By contrast, Germany, the second-largest contributor, provided $2.7 billion, or about 8% of global funding.

The Trump administration, through its Department of Government Efficiency, or DOGE, has slashed $60 billion in overseas assistance as part of its effort to massively cut government costs. That included shuttering the U.S. Agency for International Development (USAID) and reversing decades of U.S. foreign policy that viewed the soft power of humanitarian aid as being in America’s national interest.

That has left scores of international aid agencies scrambling to try to keep their programs going. The secretary-general said U.N. staff in the field are also taking urgent steps to protect as much of their lifesaving work as possible.

Guterres gave some examples of where U.S. cuts would affect — or already have affected — provision of critical services.

“In Afghanistan, more than 9 million people will miss out on health and protection services, with hundreds of mobile health teams and other services suspended,” he said.

In South Sudan, he said, funding has run out for programs to support people who have fled the war in neighboring Sudan. And in Ukraine, cash-based humanitarian assistance has been suspended in key regions.

“Our absolute priority remains clear,” Guterres said. “We will do everything we can to provide lifesaving aid to those in urgent need. And we will continue our efforts to diversify the pool of generous donors who support our work.”

Questioned later by reporters, Guterres’ spokesperson said the agencies had been informed by letter of the cuts, most coming from USAID’s acting deputy administrator, Peter Marocco. Spokesperson Stephane Dujarric said that U.N. officials “at a fairly senior level” had tried to talk with U.S. officials about the cuts.

“But I can’t say we’ve detected much interest in engaging on this issue,” he said.

Dujarric listed some of the agencies that have received termination letters, including the Food and Agriculture Organization (FAO), which received 27 letters; the International Office for Migration (IOM), which had 22 of 25 USAID programs terminated; and the U.N. Office on Drugs and Crime (UNODC), which had about 50 projects terminated.

“Their office in Mexico, which deals among other things with the flow of fentanyl, may have to close,” Dujarric said of UNODC. “It will impact their programs in Central America and the Darien Gap focusing on fighting human trafficking.”

UNAIDS, which provides lifesaving HIV treatment around the world, said Friday that it received a letter from Washington on Thursday terminating its agreement with UNAIDS “with immediate effect.”

This follows the decision in late January by Secretary of State Marco Rubio to continue funding UNAIDS while the U.S. foreign assistance review was ongoing and other international assistance was paused.

“This is a serious development which impacts the entire HIV response, including in the continuity of lifesaving HIV services for people living with and affected by HIV, civil society and our partners,” UNAIDS said in a statement.

Since 2003, through its PEPFAR program, the United States has helped save more than 26 million lives by investing in critical HIV prevention, treatment, care and support programs in 55 countries.

Rubio has said that going forward, all foreign aid must make America safer, stronger and more prosperous.

A State Department spokesperson said Thursday that so far more than 9,100 foreign assistance-related grants worth over $15.9 billion have been reviewed. More than 4,100 grants worth nearly $4.4 billion have been identified for elimination as part of “the America First agenda” — a 28% reduction in total grant value.

“USAID evaluated 6,200 multiyear awards with $58.2 billion in value remaining,” the spokesperson added. “At the conclusion of a process led by USAID leadership, including tranches personally reviewed by Secretary Rubio, nearly 5,800 awards with $54 billion in value remaining were identified for elimination as part of the America First agenda — a 92% reduction.”

State Department Correspondent Nike Ching contributed to this report. Some information came from The Associated Press.