The origins of Giuliani’s effort to stir up investigations in Ukraine remain shrouded in mystery. Earlier this week, he told POLITICO he was approached in November by a private investigator claiming to have information on Ukrainian interference in the 2016 election, but he declined to name the investigator or the investigator’s source.

Ukrainian officials have denied interfering in the 2016 election, a subject of intense interest for President Donald Trump, who has repeatedly accused the Ukrainian government of colluding with Hillary Clinton’s campaign, based in part on a 2017 POLITICO report about actions by Ukrainian officials that benefited Clinton.

But the investigator’s source claimed to have more information about the Ukrainians’ role in the 2016 campaign, including the creation of a dossier by British ex-MI6 officer Christopher Steele and covering up election-related hacking, according to Giuliani.

Lev Parnas, a Soviet-born, Florida-based businessman who aided Giuliani’s efforts, said the investigator approached Giuliani and Parnas with the tip while the pair were eating lunch, according to a story published Wednesday in The Washington Post.

But Giuliani says that version of events is “totally wrong.” The investigator called him, rather than approaching him in person, he said. And according to the former New York mayor, the approach happened two months before he began working with Parnas. He added that Parnas does not even know the identity of the private investigator. “Lev has no idea,” Giuliani said.

A lawyer for Parnas, John Dowd, acknowledged receipt of questions about the discrepancies but did not respond with answers.

Over the course of an hourlong interview on Wednesday, Giuliani also offered additional details about the origins of his Ukraine-related sleuthing efforts. He said that the call from the unnamed private investigator — a former assistant U.S. attorney he worked with in the Southern District of New York — came sometime in November before the 29th, when he met in person for the first time with the investigator.

After being told the identity of the investigator’s source, Giuliani said he consulted with a former State Department official, a former CIA official, and an American rabbi, all of whom, he said, vouched for the source’s credibility. Giuliani, who previously told POLITICO he had known the source vaguely years ago, said the investigator’s source is an American of Ukrainian descent.

Giuliani said he did not begin working with Parnas until January.

He also said he spoke with Viktor Shokin, a Ukrainian former prosecutor general fired at Joe Biden’s urging, by video chat for the first and only time on Jan. 23. That timeline contradicts previous reporting and the whistleblower complaint of an intelligence officer, which places the Giuliani-Shokin call in late 2018.

But Giuliani decried the focus on the details of his efforts, saying scrutiny should instead be falling on Joe and Hunter Biden, whose activities in Ukraine he has repeatedly claimed are corrupt, despite a lack of evidence that Hunter Biden’s dealings in the country influenced his father’s official actions.

“When you start asking me about petty little facts,” Giuliani said, “I start to worry you're burying the lead.”

Katya Gorchinskaya contributed to this report.