Wire services including Reuters and Bloomberg News will no longer hold a permanent slot in the small pool of reporters who cover US President Donald Trump, the White House has said, as it moves to exert greater control over who gets to ask him questions and report on his statements in real time.

The decision comes after the Trump administration last week lost a court challenge brought by another wire service, the Associated Press, over its earlier exclusion from the press pool.

The pool typically consists of about 10 outlets that follow the US president wherever he goes, whether it is a meeting in the Oval Office where he makes statements or answers questions, or trips at home or abroad.

Under the new policy, wire services will lose their customary spot in the pool and will instead be part of a larger rotation with about 30 other newspaper and print outlets.

Given their mission to deliver real-time information to other news organisations and readers, wire services tend to cover the US president and the White House more closely on a daily basis than most outlets.

Other media customers, particularly local news organisations that have no presence in Washington, rely on the wires for up-to-date reporting, video and audio.

"Reuters news coverage reaches billions of people each day, mostly through the thousands of news organisations around the world that subscribe to Reuters services," a Reuters spokesperson said.

"It is essential to democracy that the public have access to independent, impartial and accurate news about their government. Any steps by the US government to limit access to the president threatens that principle, both for the public and the world’s media."

Reuters remains committed to covering the White House in an impartial, accurate and independent way, the spokesperson added.

And AP said the administration's actions were a grave disservice to the American people.

"We are deeply disappointed that the administration has chosen to restrict the access of all wire services, whose fast and accurate White House coverage informs billions of people every single day, rather than reinstate The Associated Press to the wire pool," spokesperson Lauren Easton said in a statement.

Until the current administration, the three wire services – AP, Bloomberg and Reuters – were all standard members of the pool. But the White House barred AP in February after it refused to refer to the body of water south of the United States as the "Gulf of America" as Trump had ordered it be called. (Reuters)