KYIV, Ukraine — A week after the Trump administration ordered a sweeping halt to U.S. foreign development aid, the effect is already being felt in war-torn Ukraine. Several humanitarian organizations say they have been forced to suspend operations, including assistance to war veterans and internally displaced people.

The orders, which were issued while the Trump administration conducts a 90-day audit of foreign aid, have sent a chill through humanitarian organizations in Ukraine, which depend on such assistance.

The United States, the largest single source of aid to Ukraine, has provided more than $37 billion in humanitarian aid, development assistance and direct budget support since the beginning of the war nearly three years ago through its Agency for International Development, also known as USAID.

Yuriy Boyechko, the founder and CEO of Hope for Ukraine, which works with U.S.-funded Ukrainian groups to supply firewood to front-line residents, said the impact of the halt in funding would be immediate. Deliveries will stop suddenly, he said, leaving people on their own in the middle of winter.

“They’re going to feel the effect of this next week,” Boyechko said. “This is just extremely harmful because you have millions of people in front-line areas near Kherson and Kharkiv who have been living without light for a long time. For them, firewood has been the only source of heat and a way to prepare food.”

Ivona Kostyna, chair of Veteran Hub, an organization that supports veterans and their families, said that the organization had stopped two major programs: one that liaises with Ukrainian employers on employment policies for veterans, and another that provides space for veterans.

“It is on pause, but in fact for us, 90 days of pause means losing our team, our space, our clients’ trust,” she said.

After Russia’s full-scale invasion of Ukraine in February 2022 set off by some accounts the largest refugee crisis in Europe since World War II, European nations shouldered most of the burden of taking in refugees who fled Ukraine. The United States, for its part, helped to limit the flow of refugees by funding humanitarian programs that assisted internally displaced people.

A USAID spokesperson in Washington confirmed Tuesday to The New York Times that all programs and grants without a waiver approved by the secretary of state had been paused for 90 days, while the audit is continuing. The U.S. State Department said in a statement that the aid freeze was justified by the need to “refocus on American national interests” and that it would no longer “blindly dole out money with no return for the American people.”

U.S. Embassy officials in Ukraine requested exemptions to preserve aid for the country, according to Yaroslav Yurchyshyn, a Ukrainian lawmaker. The Financial Times first reported the request. Yurchyshyn expressed concern that programs providing emergency food aid would have to pause operations, even though they have been exempted globally from the orders. The funding “reduces pressure on migration,” he said, as people can remain in their towns when schools and municipal services like water and natural gas operate.

The aid agency has funded water system repairs and repairs for schools damaged by Russian artillery shelling.

Continuing the aid, Yurchyshyn said, will also counter “the narrative of totalitarian countries that democracies are unstable partners, and you can never be sure democracies will help you.”

An email from the State Department to one group, dated Jan. 24 and viewed by The New York Times, said that “all foreign assistance awards are immediately suspended” and that the group “must stop all work on the program and not incur any new costs” after Jan. 24.

The group was instructed to cancel as many outstanding obligations as possible.

The Trump administration’s threat to indefinitely cut all aid also has some groups fearing retribution if they speak out against the freeze.

In an email seen by the Times, ACTED, a major French organization operating in Ukraine and partly funded by the United States, instructed a Ukrainian partner group to “stop/suspend all work until further notice.”

It added that the group should not “communicate and comment publicly,” warning that “organizations may be subject to sanctions globally.”

A manager from the Ukrainian partner group, speaking anonymously due to concerns about retaliation, said the directive would force her to lay off nearly 100 employees immediately and not pay their salaries, which are due by the end of the month.