Fresh signs of trouble among Donald Trump’s closest aides emerged on Friday as the host of one of America’s most watched morning shows claimed Steve Bannon, White House chief strategist, was effectively running the country and briefing against the president’s son-in law.

Tensions between Mr Bannon, known for his populist programme of economic nationalism, and the more moderate Jared Kushner, who is married to Mr Trump’s daughter Ivanka, have erupted repeatedly in recent weeks.

Now Joe Scarborough, host of MSNBC’s Morning Joe, says the US withdrawal from the Paris climate accord is evidence that the former head of Breitbart News was running the administration.

"So Steve Bannon is now the president of the United States, and that was more clear yesterday than ever before," he said.