Donald Trump came out fighting last night as he slated his former “fixer” Michael Cohen and praised ex-campaign chief Paul Manafort as a day of high courtroom drama saw his presidency dealt what could go down in history as a double whammy of fatal blows.

Within the space of a few hours Mr Trump’s tenure in the White House suffered strike after strike, with the dramatic conclusion of two separate investigations into former close allies, both key figures in Special Counsel Robert Mueller’s investigation into alleged Russian election interference.

A disastrous day for the US President, which saw mounting calls for his impeachment, began in Virginia with his former campaign chairman Manafort being sensationally found guilty of eight charges of tax and bank fraud.

It followed a case which, bizarrely, saw items of clothes from his wardrobe – including an $11,000 ostrich coat – paraded before the jury. He now faces up to 80 years in jail.

At about the same time in New York, Mr Trump’s former personal attorney, Cohen, stunned a federal courtroom when he admitted he paid hush money to two women alleged to have had affairs with the then presidential candidate in the run-up to the 2016 US elections.

He said he had made the payments “at the direction of the candidate,” and had done so specifically to influence the outcome of the election.

Both cases had emerged from Mr Mueller’s far-reaching investigation into Mr Trump’s inner circle as he probes suggestions of Russian meddling in the 2016 election and possible obstruction of justice by the President.

Mr Trump has dismissed Mueller’s inquiry as a “hoax”.

While Manafort’s charges do not directly link to Special Counsel’s probe, they are being seen as a major victory for investigators.

Meanwhile, self-proclaimed Trump “fixer” Cohen’s decision to admit a string of charges, including tax evasion and two campaign finance violations, followed a warning he could face more than 12 years in prison.

Mr Trump quickly took to Twitter to heap praise on Manafort as “a brave man” who had refused to break under legal pressure, and to warn his followers: “If anyone is looking for a good lawyer, I would strongly suggest that you don’t retain the services of Michael Cohen!”

However, his former attorney’s shock admission is set to open the door to investigators seeking further details of his pre-election dealings, and raises the possibility of Manafort opting to work with Mueller’s team in the hope of a lighter sentence.

Cohen, Mr Trump’s confidante and keeper of his professional and personal secrets during his time in New York, is believed to have a catalogue of documents and alleged recordings related to his former employer.

Cohen’s attorney, Lanny Davis, suggested his client was set to open up about what he knows to Mueller’s investigators. “Under no circumstances would he accept a pardon from Mr. Trump,” Davis said, adding that the president “not only directed a crime, he’s part of a cover up.”

Earlier, the President had come out swinging as he arrived in Charleston, West Virginia, for a pre-scheduled rally, where he continued his attack on

Mueller and the Justice Department, calling Manafort’s conviction “very sad,” while continuing to assail Mueller’s inquiry as a “witch hunt.”

But legal analysts said the rapidly unfolding developments gave new legitimacy to Mueller’s work that even the most ardent Trump backers could not ignore.

“The saying goes that justice rides a slow horse, but it gets there eventually,” said Bruce Udolf, a criminal defence attorney in Florida who served as an associate independent counsel during the Whitewater investigation. “It got there Tuesday.”