President Trump on Saturday gave his backing to Rudy Giuliani, his personal attorney, after reports that the former New York City mayor is being investigated by federal prosecutors for possibly lobbying violations in relation to his work in Ukraine.

“So now they are after the legendary ‘crime buster’ and greatest Mayor in the history of NYC, Rudy Giuliani,” Trump tweeted. “He may seem a little rough around the edges sometimes, but he is also a great guy and wonderful lawyer.”

TWO GIULIANI ASSOCIATES LINKED TO UKRAINE INVESTIGATIONS INDICTED ON CAMPAIGN FINANCE CHARGES

The New York Times reported Friday night that prosecutors in Manhattan are investigating whether Giuliani broke lobbying laws in his dealings with Ukraine. They are reportedly examining Giuliani’s efforts to oust then-U.S. Ambassador to Ukraine Marie Yovanovitch.

Earlier this week, two associates of Giuliani were indicted for campaign finance violations. Lev Parnas and Igor Fruman are accused of using a limited liability company to make political contributions related to American elections, in violation of FEC prohibitions against contributions from foreign nationals.

Both men have been linked to Giuliani’s efforts to conduct investigations into former Vice President Joe Biden’s, and his son Hunter’s, dealings in the country -- particularly connected to Hunter’s ties to a Ukrainian gas company. Giuliani has acknowledged that both men "logistically helped" in his collection of evidence against Hunter Biden, and that they helped connect him with former Ukrainian top prosecutors Viktor Shokin and Yuriy Lutsenko.

The arrests came amid a growing impeachment inquiry related to President Trump’s July 25 phone call with Trump and Ukrainian President Volodymyr Zelensky. In that call, Trump asked the premier to “look into” the allegations about Biden. Opponents have accused Trump of withholding military aid to pressure the Ukrainians into investigating a political rival -- something Trump denies.

EX-GOP CONGRESSMAN SAYS HE'LL DONATE CONTRIBUTIONS FROM ARRESTED GIULIANI ASSOCIATES

Yovanovitch, the former Ukraine ambassador who was recalled in May, told lawmakers on Friday that she was removed after “unfounded and false claims” were made against her as well as continued pressure from Trump on the State Department to remove her.

She said, as for Giuliani, she was in contact with him three times as she can recall, none related to the controversy at hand -- and said that she did not know Giuliani’s motives for going after her.

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“But individuals who may have been named in the press as contacts of Mr. Giuliani may well have believed that their personal financial ambitions were stymied by our anti-corruption policy in Ukraine,” she said

On Saturday, Trump appeared to dismiss the claims against Giuliani, as well as the impeachment inquiry as a whole -- as he has done so multiple times before.

“Such a one sided Witch Hunt going on in USA. Deep State. Shameful!” he tweeted.

Fox News' Ronn Blitzer contributed to this report.