WASHINGTON — President Donald Trump has moved to unilaterally cancel $4.9 billion in foreign aid authorized by Congress, escalating the fight over who controls the nation’s spending.

In a letter posted online late Thursday, Trump told House of Representatives Speaker Mike Johnson that he plans to withhold funding for 15 international programs.

The U.S. Constitution grants funding power to Congress, which passes legislation each year to fund government operations.

The White House must secure Congress’ approval if it does not want to spend that money. Congress did this in July when it approved the cancellation of $9 billion in foreign aid and public media funding.

The latest move — known as a “pocket rescission” — bypasses Congress entirely.

Trump budget director Russell Vought has argued that Trump can withhold funds for 45 days, which would run out the clock until the end of the fiscal year on September 30. The White House said the tactic was last used in 1977.

According to a court document filed on Friday, the money at issue was earmarked for foreign aid, United Nations peacekeeping operations, and democracy-promotion efforts overseas. Most of that had been handled by the U.S. Agency for International Development, which Trump’s administration has largely dismantled.

Democrats say the administration froze more than $425 billion in funding overall.

Most Republican lawmakers have said they support spending cuts in any form even if it erodes Congress’ authority.

But Republican Senator Susan Collins of Maine, who oversees spending legislation as chair of the Senate Appropriations Committee, said the action is illegal.

“Instead of this attempt to undermine the law, the appropriate way is to identify ways to reduce excessive spending through the bipartisan, annual appropriations process,” she said in a statement.

Senate Democratic Leader Chuck Schumer said Trump is aiming to force a government shutdown at the end of September by indicating that he is willing to ignore any spending laws passed by Congress.

“Republicans don’t have to be a rubber stamp for this carnage,” Schumer said in a statement.

(Reporting by Nolan McCaskill and Bo Erickson; additional reporting by Steve Holland and Ryan P. Jones; Editing by Andy Sullivan, Franklin Paul and Nick Zieminski)