The President of the United States had a disagreement with private lawyer Rudy Giuliani, refused to let his assistant contact him and refused to pay legal fees.

Relations between US President Donald Trump and private lawyer Giuliani, who spearheaded legal efforts to overturn the election results, have cooled significantly, according to the Washington Post.

The president is said to have been upset because Giuliani demanded $ 20,000 a day, a number that the lawyer denied but was clearly stated on the paper.

Aides suggest that the discord with Giuliani, one of Trump's most staunch supporters, contributes to the President's feelings of isolation and betrayal.

Those believed to disappoint Trump include Press Secretary Kayleigh McEnany, son-in-law and counselor Jared Kushner, Chief of Staff Mark Meadows.

Trump's refusal to pay the costs was another blow to Giuliani.

"I'm willing to bet on fame, President is ready to bet fame. In fact, we have found mistakes. Try it by fighting," Giuliani said at Trump's "Save America" rally.

Michael Sherwin, acting federal prosecutor in Washington DC, is investigating the riot.

Over the past week, Trump has suffered a series of damaging lashes.

According to the Washington Post, Trump is said to be lonelier than ever.

The rift with Trump could spoil Guiliani's lingering hopes of getting the President's pardon.