Cohen joins supporters praying over during a campaign stop at the New Spirit Revival Center church in Cleveland Heights, Ohio
Donald Trump's personal attorney Michael Cohen stands behind Trump as he runs for president while a group of supporters lay hands on Trump in prayer during a campaign stop at the New Spirit Revival Center church in Cleveland Heights, Ohio, U.S. September 21, 2016. Reuters

Donald Trump sued his ex-lawyer Michael Cohen on Wednesday seeking at least $500 million in damages, as the former U.S. president steps up attacks on his onetime loyal "fixer" after Cohen testified before the Manhattan grand jury that indicted Trump.

In a complaint filed in federal court in Miami, Trump accused Cohen of failing to keep confidential attorney-client communications private and profiting by "spreading falsehoods" about him in books and podcasts.

Lanny Davis, a lawyer for Cohen, called Trump's lawsuit "frivolous." Trump often over the years has filed suits against various adversaries.

"Mr. Trump is once again using and abusing the judicial system as a form of harassment and intimidation against Michael Cohen," Davis said.

The lawsuit comes as Cohen, who once said he would "do anything" to protect Trump, appears poised to become a star witness against him at a possible criminal trial in New York on the charges unsealed last week. Trump, who is running for the 2024 Republican presidential nomination, pleaded not guilty to 34 counts of falsifying business records. It marked the first time a former U.S. president was charged with a crime.

Prosecutors led by Manhattan District Attorney Alvin Bragg, a Democrat, have said Trump covered up his reimbursement of Cohen for $130,000 in hush money paid before the 2016 election to porn star Stormy Daniels, who has said she had a sexual encounter with Trump in 2006. Trump denies that any such relationship occurred.

Trump's lawsuit said Cohen wrongfully called Trump "racist" in the disbarred lawyer's 2020 book, entitled "Disloyal," and fabricated conversations with Trump from when he served as his attorney.

"The timing of Disloyal's release, just prior to the November 3, 2020 Presidential Election, suggests that (Cohen) intended to improperly disclose (Trump's) confidences when it would be most lucrative to do so - and while Disloyal would be sure to have the most damaging reputational effect," the lawsuit said.

Trump lost the election to Democrat Joe Biden.

'I AM ASHAMED'

Cohen was a top executive at Trump's real estate company and then worked as his personal lawyer when Trump became president in 2017. Once known for intense loyalty to Trump, Cohen has become a harsh critic and has assisted law enforcement agencies and lawmakers investigating his former boss.

"I am ashamed because I know what Mr. Trump is," Cohen told a U.S. congressional committee in 2019. "He is a racist. He is a con man. He is a cheat."

Cohen in 2018 pleaded guilty to violating federal election law through the $130,000 payment to Daniels. He was sentenced to three years in prison for that and other crimes, including cheating on his personal taxes and lying under oath to Congress about when the Trump Organization stopped working on a proposed building project in Russia.

Referring to Daniels by her real name Stephanie Clifford, Trump's lawyers said Trump intended the payment to her "to protect his family from the malicious and false claims made by Clifford."

The criminal case is one of several legal woes Trump faces including investigations into attempts to overturn his 2020 election loss and into his removal of government documents from the White House after leaving office.

New York State Attorney General Letitia James last year filed a civil lawsuit against Trump and his three adult children for fraud, accusing them of misstating the values of real estate properties to obtain favorable loans and tax benefits. Trump also sued James after she filed that case.

Trump last week said Cohen had failed to appear for a deposition by Trump's legal team as part of that lawsuit, which is scheduled to go to trial on Oct. 2. Justice Arthur Engoron set a hearing for April 21 to consider whether to order Cohen to testify.

Trump filed a suit against James seeking to halt her civil case, but a judge dismissed it, writing that there was "no evidence" that the investigation was undertaken in bad faith.

In another case, a judge in January ordered Trump and his lawyers to pay nearly $1 million for filing a "completely frivolous" suit accusing Hillary Clinton and other Democrats of trying to rig the 2016 U.S. presidential election.