President Trump's former personal attorney John Dowd is in talks to represent two businessmen born in the former Soviet Union who played a central role in Rudy Giuliani's inquiries into Ukraine.

Dowd is expected to be retained by Ukraine-born Lev Parnas and Belarus-raised Igor Fruman as early as Friday, a source with direct knowledge told the Washington Examiner.

Three House committees issued Parnas and Fruman preservation of evidence orders Monday as part of an impeachment inquiry into Trump. The South Florida-based businessmen donated hundreds of thousands of dollars to Republicans since Trump's election and helped guide Giuliani's attempts to investigate alleged Democratic links to corruption in Ukraine.

A whistleblower's disclosure that Trump pressured Ukraine's president to cooperate with Giuliani during a July 25 phone call triggered the official impeachment inquiry last week.

Parnas and Fruman helped arrange a January meeting in New York between then-Ukrainian Prosecutor General Yuri Lutsenko and Giuliani, according to reports. The men reportedly visited Lutsenko in Kiev early this year.

Lutsenko convinced Giuliani that he had evidence of corruption involving Democratic presidential candidate Joe Biden and his son Hunter. As vice president, Biden forced the ouster of a previous Ukrainian prosecutor while his son served on the board of an energy company that had been under investigation.

The Associated Press reported that Parnas and Fruman transferred $325,000 in May 2018 from a company they control to America First Action, a political action committee allied to Trump. Parnas posted to Facebook a photo of himself with Trump in the president's official residence the same month as the donation. The men also donated $100,000 to Trump and GOP candidates.

Neither businessman could immediately be reached for comment and Dowd declined to comment on the record. Giuliani, who this week hired former Watergate prosecutor Jon Sale to represent him in congressional inquiries, referred to the duo as "my clients" in a May tweet. He did not immediately respond to an inquiry about whether he currently represents the men.

Parnas told the Miami Herald on Thursday that Giuliani was his lawyer and that, "I got certain information and I thought it was my duty to hand it over."

Dowd left Trump's legal team in March 2018, about a month before Giuliani joined. Dowd urged Trump to cooperate with special counsel Robert Mueller and refrain from attacking him publicly. He would represent Parnas and Fruman during congressional investigations.

