Rudy Giuliani is reportedly under federal investigation for possible campaign violations

• President Donald Trump's personal lawyer Rudy Giuliani is reportedly being probed by federal investigators over possible campaign finance violations, Bloomberg reported on Thursday.
• Three US officials told Bloomberg that in addition to the violations, investigators are looking into whether Giuliani failed to register as a foreign agent.
• Giuliani was named dozens of times in the August whistleblower complaint that sparked an impeachment inquiry, and testimony from witnesses in the impeachment inquiry also also mentions the role of the former New York mayor in the US dealings with Ukraine.
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President Donald Trump's personal lawyer Rudy Giuliani is being probed by federal investigators over possible campaign finance violations, Bloomberg reported on Thursday.

Three US officials told Bloomberg that investigators are looking at possible campaign finance violations and whether Giuliani failed to register as a foreign agent. One official told the outlet that the investigation into his financial dealings could also include possible charges related to bribery of foreign officials and conspiracy. The New York Times previously reported that investigators were looking into whether Giuliani broke any foreign lobbying laws.

Neither Giuliani nor his lawyers responded to Bloomberg's request for comment. Insider could not immediately reach his attorneys for comment.

Giuliani, who is a central figure to impeachment proceedings against Trump, lawyered up last week in apparent preparation for intensified scrutiny over his work in Ukraine.

The impeachment inquiry, which officially transitioned into its public phase this week, is centered around a July 25 phone call between Trump and Ukrainian President Volodymyr Zelensky.

The call was the subject of an anonymous whistleblower complaint filed in August that accused Trump of "using the power of his office to solicit interference from a foreign country in the 2020 US election," in particular asking Ukraine to investigate former Vice President Joe Biden and his son Hunter Biden to aid Trump politically.

Giuliani is named dozens of times in the complaint, and testimony from witnesses in the impeachment inquiry also highlights the former New York mayor's apparent role in Ukraine.

In the days leading up to the July 25 call, Trump ordered his administration to withhold nearly $400 million in military aid to Ukraine. Among other things, House investigators are working to establish whether there was quid pro quo arrangement, in which Trump would release the aid money to Ukraine in exchange for political investigations.

On Monday, a lawyer for Giuliani's former associate, businessman Lev Parnas, told The New York Times that he was sent to Ukraine by Giuliani to broker a quid pro quo arrangement with the Ukrainian government so that they would investigate the Bidens. The attorney added that his client, who was arrested last month for campaign finance violations, believed Giuliani was acting on Trump's authorization. Another of Giuliani's associate Igor Furman was charged last month with campaign finance violations.

Trump has denied that a quid pro quo deal was ever sought with Ukraine and has maintained that his phone call with Zelensky was "perfect."