The host, Jonathan Capehart, was questioning the former prosecutor and New York City Mayor over his dealings with Andrii Derkach, a businessman and member of the Ukrainian parliament who was recently sanctioned by the U.S. Treasury Department “for attempting to influence” the 2020 presidential election.

A press release from the department said Derkach “has been an active Russian agent for over a decade, maintaining close connections with the Russian Intelligence Services. Derkach has directly or indirectly engaged in, sponsored, concealed, or otherwise been complicit in foreign interference in an attempt to undermine the upcoming 2020 U.S. presidential election.”

The Treasury Department said that from at least late 2019 through mid-2020, Derkach “waged a covert influence campaign centered on cultivating false and unsubstantiated narratives” regarding U.S. officials in the upcoming election, which sparked corruption investigations in both Ukraine and the United States.

These included promoting unsubstantiated allegations of corruption against Joe Biden and his son Hunter Biden, who once sat on the board of Ukrainian natural gas company Burisma.

In December 2019, Giuliani met with Derkach in Ukraine, to discuss a joint U.S.-Ukraine investigation into corruption in Ukraine, The Washington Post reported.

During Saturday’s MSNBC interview, Giuliani said he denied working with Derkach, saying that he simply interviewed him about Joe Biden, Mediaite reported.

Capehart asked Giuliani whether he had ever paid or facilitated payments to Derkach or vice versa.

“No, I don’t pay people for information Jonathan,” Giuliani responded. “You’ve known me long enough to know I won’t do that. You covered me when I was mayor and U.S. attorney. You know I’m not a dishonest person.”

The MSNBC host continued by saying, “I’m glad you brought that up,” noting that he had covered the former mayor and prosecutor since his early days on the New York Daily News editorial page.

“As I mentioned you made your name as the SDNY [Southern District of New York] federal prosecutor, you were mayor of New York City twice. My point here is the idea that a former Federal prosecutor of SDNY, former two-term mayor of New York City, a person who has a national security firm. How… I’m trying to understand how someone of your stature and career—what happened to you, Mayor Giuliani?” Capehart said.

“Why are you out here spinning conspiracy theories and lies and interfering with an American election? What happened to you?”

“Nothing happened to me,” Giuliani said. “They’re not conspiracy theories. I’m not interfering with an American election. Indicting Steve Bannon is interfering with an American election but that’s okay. But putting out a report that Biden’s a crook isn’t.”

Capehart responded by saying that Giuliani was “running around the world” trying to find evidence that will undermine the Democratic Presidential nominee— “and you’re not finding any that can’t be debunked by fact-checkers all over the country.”

But Giuliani also denied these claims, describing them as “absolutely wrong” while also criticizing the news network.

“All you do on MSNBC is not cover it,” Giuliani said, “you cover it up.”