Republican and Democratic lawmakers have joined forces to oppose moves by the White House that critics fear could lead to sharp cuts in foreign aid for health, peacekeeping, narcotics control, and other programs.
Senior members of both parties sent a letter on August 9 to the Office of Management and Budget (OMB) expressing "deep concern" after it instructed the State Department and U.S. Agency for International Development (USAID) to freeze around $4 billion in their budgets until it reviews any money that hasn't yet been spent.
Critics have said the freeze could be the first step in making cuts to foreign aid.
In the letter, the lawmakers wrote that "these funds, which were appropriated by Congress and signed into law by the president following lengthy, bipartisan negotiations, are essential to promoting U.S. global leadership and protecting the security of the American people."
The freeze impacts 10 bank accounts overseen by USAID and the State Department, a senior administration official told RFE/RL.
The OMB made the request to USAID and State Department on August 3 and has yet to receive information about how much is currently in those accounts and how they plan to use the money.
The fiscal year ends on September 30.
Funding for a Pakistani space initiative and Uzbek education program are two of the projects funded by the 10 accounts under review.
The chairmen and ranking members of the Senate Foreign Relations Committee and House of Representatives Foreign Affairs Committee urged the heads of the OMB to make money available right away.
Republicans in both houses of Congress have typically been extremely supportive of Trump's policies, although many have spoken up against moves related to foreign affairs, including his close ties to Saudi Arabia, plans to withdraw troops from Syria, and reduction in aid to Central America.
The Trump administration has made repeated efforts to reduce the amount of money Washington spends on foreign aid.
In April, the administration unsuccessfully tried to cut the budget on foreign aid and diplomacy by 23 percent.
Republican Senator Lindsey Graham, a Trump ally, called the proposal "insane."