Washington (CNN) Rudy Giuliani's financial dealings with two associates indicted on campaign finance-related charges are under scrutiny by investigators overseeing the case, law enforcement officials briefed on the matter said.

The FBI and prosecutors in Manhattan are examining Giuliani's involvement in the broader flow of money that have become the focus of alleged violations that are at the center of the allegations against Lev Parnas and Igor Fruman, the sources said. The sources did not say that Giuliani was a target of the investigation.

Giuliani told CNN he is not aware of any law enforcement scrutiny on his financial dealings with the men and he said he has not been interviewed by the FBI in the investigation.

Parnas and Fruman have emerged as major figures in the ongoing impeachment inquiry in the House of Representatives because of their relationship with Giuliani, President Donald Trump's personal attorney. Parnas was Giuliani's fixer in Ukraine, introducing him to current and former officials as far back as 2018, CNN has reported

Starting in November 2018, Giuliani told CNN, Parnas and Fruman introduced him to former and current Ukrainian officials who provided information that Giuliani claims is damaging to some of Trump's political enemies, including former Vice President Joe Biden. House Democrats have subpoenaed documents from Giuliani, Parnas, and Fruman relating to those interactions.

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