Melanie Eversley

USA TODAY

President Trump, increasingly under fire for his campaign's alleged ties to Russia, is expected to hire Wall Street lawyer Marc Kasowitz, according to various news organizations.

Kasowitz's website describes him as the "toughest lawyer on Wall Street." Former U.S. Sen. Joe Lieberman is one of his partners in his firm.

Trump is expected to retain Kasowitz to help represent him in the federal investigation into alleged ties between his presidential campaign and Russia, Fox Business Network and ABC News reported. Kasowitz has represented Trump in the past.

The revelation comes a few days after former FBI Director Robert Mueller was named special counsel in the federal investigation into ties between Russia and the Trump campaign. Mueller's appointment came after former FBI Director James Comey said the president pressured him to ease off of an investigation into former National Security Adviser Michael Flynn.

Kasowitz represented Trump last year after The New York Times reported that multiple women claimed Trump sexually assaulted them.

In a piece published in January, The Wall Street Journal described Kasowitz as "Donald Trump's go-to guy for his toughest legal battles."

Trump organization executive vice president and chief legal officer Alan Garten told the Journal, "Marc's always been a great guy you go to when you have complex, intricate legal problems."

Kasowitz founded his firm in 1993 and grew it into a 270-lawyer operation with revenue of more than $200 million, The Wall Street Journal reported. In the past, he's helped Trump keep his divorce records sealed and restructure debt tied to his Atlantic City casinos, according to the Journal.

Kasowitz could not be reached late Tuesday. The White House press office also could not be reached.