President Trump on Thursday signed an executive order aiming to cut federal funding for NPR and PBS, accusing the outlets of producing biased coverage and “left-wing propaganda.”

Mr. Trump instructed the Corporation for Public Broadcasting, which funds public broadcasters in the United States, to end federal funding for NPR and PBS, to the extent allowed by law. The outlets receive only a small portion of their funding from Congress, with the rest coming from donors and sponsors.

The immediate impact of the order was unclear. The Corporation for Public Broadcasting, a taxpayer-backed, private entity created by an act of Congress, is funded two years in advance to protect it from political maneuvering.

The executive order was the latest move by the Trump administration against what it described as biased public media. The White House released a document accompanying the order on its website, criticizing the two broadcasters’ coverage of, among other topics, the Covid-19 pandemic and Hunter Biden, the son of former President Joseph R. Biden Jr.

Mr. Trump ordered the Corporation for Public Broadcasting and all federal agencies to also cut indirect funding by forbidding public radio and television broadcasters that receive federal funds from using that money for PBS or NPR programs.

The chief executives of NPR and PBS testified before Congress in March, a heated hearing in which Republicans assailed them for what they described as liberal bias.

The White House wants Congress to take back more than $1 billion for two years that has been allocated for the Corporation of Public Broadcasting. Mr. Trump’s order on Thursday instructed the board of the corporation to “cancel existing direct funding to the maximum extent allowed by law” and “decline to provide future funding.”

NPR said in a statement early Friday that the broadcaster’s editorial practices and decisions are independent and free from outside influences, including political parties.

“Eliminating funding for the Corporation for Public Broadcasting would have a devastating impact on American communities across the nation that rely on public radio for trusted local and national news, culture, lifesaving emergency alerts and public safety information,” the statement said.

PBS and the Corporation for Public Broadcasting did not immediately respond to requests for comment made outside business hours.

Paula Kerger, the PBS chief executive, said in an interview that aired this week that about 15 percent of the overall budget for public broadcasters comes from the federal government.

“This is different than many other public broadcasters around the world, which are largely state-supported,” she said on “PBS NewsHour.” “We are not.”

Nevertheless, in 2011 NPR assembled a 36-page document that detailed exactly what would happen if the Treasury stopped cutting checks to the Corporation for Public Broadcasting, the government-backed company that supports NPR and PBS. The document is bleak. It describes a precarious radio system that will bear the blow poorly, with consequences for listeners across the United States.

Independent member stations get most of the money devoted to public radio. That makes them more vulnerable than NPR, which says it gets only 1 percent of its budget from Congress.

Public television in the United States would likely be in worse shape because PBS receives much more of its budget — about 15 percent of $373 million — from the federal government.

The Corporation for Public Broadcasting sued the Trump administration this week, accusing it of illegally trying to fire three members of its board. The administration had not offered any justification for the dismissals.

Benjamin Mullin contributed reporting.