In a drama that played out simultaneously across two US cities yesterday, two key aides each faced eight separate charges stemming from a federal investigation into the 2016 presidential election.

In New York, Trump's long-time attack-dog fixer Michael Cohen pled guilty to eight counts including making illegal campaign contributions. In a sensational twist he pointed to the president as a co-conspirator.

Cohen pled guilty to illegally making pre-election hush payments, including to porn star Stormy Daniels, who says she had an affair with Trump. But as part of a plea deal Cohen said he acted "in coordination and at the direction of a candidate for federal office."

"I participated in this conduct with the purpose of influencing the election," a visibly crestfallen Cohen told the judge, his voice trembling at times as he addressed the packed courtroom.

That admission put Trump himself in legal jeopardy and raised the prospect that a trusted lieutenant is ready to spill secrets, gathered over decades, in exchange for a reduced sentence.

The White House refused to comment on Cohen's allegation, with press secretary Sarah Sanders tersely telling reporters: "Refer you to the President's outside counsel."

While the Cohen drama was unfolding in New York, a jury in Virginia found Trump's one-time campaign chairman Paul Manafort guilty on eight counts including bank fraud, tax fraud and a failure to declare foreign bank accounts.

Trump expressed regret, calling Manafort "a good man." "I feel very sad about that," Trump told reporters as he arrived in West Virginia for a rally, claiming the conviction was part of a "witch hunt" after the 2016 election. "It's a very sad thing that happened, this has nothing to do with Russian collusion."

Trump also sought to distance himself from Manafort -- who was instrumental in the 72-year-old securing the 2016 Republican nomination. "He worked for many, many people," said Trump, citing campaigns for former president Ronald Reagan and vice presidential candidate Bob Dole.

But it is Cohen's decision to enter a plea deal that may pose the most problems for the White House. While it is US legal tradition that the president cannot be tried, the allegation, if proven will only increase calls for his impeachment.

Questioned by a federal judge in Manhattan, Cohen indicated he had paid sums of USD 130,000 and USD 150,000 each to two women who claimed they had affairs with Trump. The two women are believed Stormy Daniels and Karen McDougal, a Playboy model who the president also denies having an affair with. Cohen said he made the payments "at the request of a candidate" to silence "information that would be prejudicial to the candidate and the campaign."

In addition to two counts of violating campaign finance laws, Cohen pleaded guilty to five counts of tax fraud and one of bank fraud during the hearing before US District Judge William Pauley. The judge informed the 51-year-old Cohen he faced a maximum of 65 years of imprisonment, with his sentenced set to be handed down on Dec 12.

The US president had spent much of yesterday cooped up at the White House, as rainstorms raged outside and the two high profile legal cases with profound implications for his presidency reached their coda.

At a courthouse close to Washington, jurors spent four days deliberating on the 18 charges against Manafort. While the jury was unable to reach a verdict on 10 counts, prompting the judge to declare a partial mistrial, Manafort was found guilty on the eight remaining charges.

These included five counts of making false income tax returns, two counts of bank fraud and one of failure to report foreign bank and financial accounts.

Each of the bank fraud counts carries a significant maximum sentence and the 69-year-old could theoretically live out the remainder of his years in prison -- though a legal expert contacted by AFP predicted his sentence would in reality run to under a decade.