FILE PHOTO: Rudy Giuliani is seen ahead of U.S. President Donald Trump introducing his Supreme Court nominee in the East Room of the White House in Washington, U.S., July 9, 2018. REUTERS/Leah Millis Reuters

Rudy Giuliani, personal lawyer to President Donald Trump, has hired representation as federal prosecutors close in on him amid the broader impeachment into the president.

Giuliani tweeted on Wednesday that he’s „represented and assisted by Robert Costello and the Pierce Bainbridge firm in particular, Eric Creizman and Melissa Madrigal.“

Giuliani was previously represented by Jon Sale, a law school classmate and Watergate prosecutor.

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President Donald Trump’s personal lawyer, Rudy Giuliani, has new representation as he faces increasing pressure from the federal government related to his work in Ukraine.

Giuliani on Wednesday tweeted that he’s „represented and assisted by Robert Costello and the Pierce Bainbridge firm in particular, Eric Creizman and Melissa Madrigal.“

Costello’s name has come up before in relation to Trump, Giuliani, and the president’s former personal lawyer and fixer, Michael Cohen, who is now in prison. Reports in March surfaced suggesting that Costello had indicated to Cohen that the president was considering the possibility of pardoning him, but Costello vehemently denied this at the time.

Costello confirmed to Insider that he’s representing Giuliani.

Pierce Bainbridge did not immediately respond to a request for comment from Insider.

Giuliani is at the center of a scandal that poses an existential threat to Trump’s presidency and involves a whistleblower complaint from a US intelligence official that accuses the president of abusing the power of his office to urge Ukraine to investigate former Vice President Joe Biden and his son, Hunter Biden.

The former New York mayor is mentioned dozens of times in the complaint, which has catalyzed an impeachment inquiry into Trump in the House. Testimony from witnesses in the impeachment inquiry also heavily implicate Giuliani, according to transcripts released by House investigators.

Correspondingly, Giuliani is reportedly under criminal investigation in the Southern District of New York over the role he played in Marie Yovanovitch getting recalled under dubious circumstances as the US ambassador to Ukraine. The investigation focuses on whether Giuliani broke foreign lobbying laws as part of these efforts, The New York Times reported last month.

On top of this, there’s reportedly an FBI counterintelligence probe into whether a foreign influence operation sought to use Giuliani’s financial interests in Ukraine as a means of gaining access to the White House.