The White House on Tuesday stripped journalists of the nearly century-old power to decide which of them cover U.S. presidential events, with Donald Trump boasting that he was now "calling those shots" on media access.

Trump's spokeswoman Karoline Leavitt made the surprise announcement at a daily briefing, saying that the independent White House Correspondents' Association (WHCA) would no longer have a "monopoly" on choosing members of the "press pool."

The press pool is a small group of reporters that covers the U.S. president in often cramped spaces like the Oval Office and Air Force One, and shares their material with other news organizations.