President Donald Trump‘s personal attorney, Rudy Giuliani, the former mayor of New York City, is under scrutiny for having worked with an active Russian agent, according to the United States Department of the Treasury. Andriy Derkach, a Ukrainian parliamentarian, was just placed on a list of “Russia-linked election interference actors” for having been in close connection with Russian Intelligence Services. The finding, which was likely discovered by U.S. intelligence investigations,  indicates that Derkach has engaged or otherwise been complicit in foreign interference with the upcoming 2020 U.S. presidential election. Officials told Congress that Derkach is spreading claims about corruption in an attempt to sabotage Joe Biden‘s election campaign. These reports follow previous accounts from the summer in which the U.S. intelligence community disclosed that Derkach was assisting with Moscow’s ongoing efforts to weaken Biden’s campaign.

But it appears as though Derkach has not been working alone. Before Trump’s impeachment last year, Giuliani traveled to Ukraine to meet with Derkach and other Ukrainians who suspected Biden of acting in an inappropriate manner back in 2016, when he joined a global push for the removal of Ukraine’s top prosecutor who, at the time, was accused of corruption.

But the interaction between Giuliani and Derkach does not end there. In the past year, Giuliani has assisted the “Russian agent” in multiple press conferences that sought to further expose Biden and his supposed corrupt actions. At these conferences, Derkach played tapes of Biden talking to the Ukrainian president, although these tapes do not reveal incriminating information. Rather, these conferences were merely part of Derkach and Giuliani’s continued attempt to assert claims of corruption against Trump’s presidential opponent.

Giuliani claims he had no idea that Derkach was a Russian agent, and in an interview on Saturday on AM Joy, Trump’s personal attorney refused to answer questions on how it was possible that he was so unaware of Derkach’s political relationships.

This recent news comes as a major step by the United States government to publicly fight Russia’s continued attempts to interfere in the 2020 presidential election. Although Trump has repeatedly denied any claims that Russia has interfered in the 2016 election, United States intelligence services continue to point to information that reveals otherwise.