(Adds comment from legal expert)

By Brendan Pierson

NEW YORK, Aug 21 (Reuters) - U.S. President Donald Trump's former personal lawyer Michael Cohen testified on Tuesday that Trump had directed him to commit a crime by arranging payments ahead of the 2016 presidential election to silence two women who said they had affairs with Trump.

Cohen's voice cracked several times as he pleaded guilty to eight criminal charges in federal court in Manhattan, including tax evasion, bank fraud and campaign finance violations. Facing up to five years in prison, the admissions were a dramatic change from Cohen's earlier boasts that he was Trump's "fixer" and would "take a bullet" for the president.

Most legal experts say a sitting president cannot be indicted for a crime, but the Constitution allows Congress to impeach and remove a president from office for "high crimes and misdemeanors."

Cohen’s accusation increases political pressure for Trump ahead of November’s congressional elections where Democrats are trying to regain control of the House of Representatives and Senate.

Cohen told Judge William Pauley III that "in coordination with, and at the direction of, a candidate for federal office" he arranged payments to two women for their silence "for the principal purpose of influencing the election."

Adult-film star Stormy Daniels was given $130,000 and former Playboy model Karen McDougal was paid $150,000.

Cohen did not name Trump in court, but his lawyer, Lanny Davis, said afterward that he was referring to the president.

"Today he (Cohen) stood up and testified under oath that Donald Trump directed him to commit a crime by making payments to two women for the principal purpose of influencing an election," Davis said in a statement.

"If those payments were a crime for Michael Cohen, then why wouldn't they be a crime for Donald Trump?" Davis said.

Trump has denied having affairs with the women. His lawyer Rudy Giuliani has said the payments were made to spare Trump and his family embarrassment and were unrelated to the campaign.

Trump did not mention Cohen at a rally in West Virginia hours later.

Giuliani lashed out at Cohen on Tuesday, calling him a "devious little rat" and saying he had a history of lying.

"I think the president is absolutely in the clear," Giuliani told Reuters. "The Cohen thing is over."

Under U.S. election law, campaign contributions, defined as things of value given to a campaign to influence an election, must be disclosed. A payment intended to silence allegations of an affair just before an election could constitute a campaign contribution, which is limited to $2,700 per person per election, some experts said.