NEW YORK (NewsNation Now) — Rudy Giuliani denied Thursday he had ever represented a Ukrainian national, a day after federal agents searched his Manhattan apartment and office as part of a probe into his business dealings in Ukraine.

Agents searched Giuliani’s New York City home and office Wednesday. The warrants, which require approval from the top levels of the Justice Department, signify prosecutors believe they have probable cause that Giuliani committed a federal crime — though they don’t guarantee charges will materialize.

Giuliani said the 6 a.m. search, which he said involved seven FBI agents, was unnecessary because he offered for two years to provide federal prosecutors his electronic devices and to “talk it over with them.” He claimed the search warrant included an allegation that he had failed to register as a foreign agent, a violation of lobbying laws.

“I’ve never represented a Ukrainian national or official before the United States government,” Giuliani said in an interview on Fox News.

Giuliani’s lawyer, Robert Costello, has previously said proposed meetings between investigators and Giuliani’s legal team didn’t take place because prosecutors wouldn’t agree to a precondition that they first disclose more about the probe. However, it would be rare for prosecutors to give up detailed information to a potential criminal defendant before charges are filed, or to rely on that person to voluntarily produce electronic files thought to contain incriminating evidence.

The federal probe is examining Giuliani’s interactions with Ukrainian figures and whether he violated a federal law that governs lobbying on behalf of foreign countries or entities. The investigation has been ongoing for more than a year over his Ukrainian business dealings while serving as former President Donald Trump’s attorney. He has not formally been accused of any wrongdoing.

On the day of the raids, Giuliani’s son, Andrew, told reporters the investigation was completely political. Asked to clarify his remarks on Thursday’s edition of NewsNation’s ‘The Donlon Report,’ the younger Giuliani, who’s mulling a run for Governor of New York, said, “All I can tell you is that I continually see people who are associated with Donald Trump and the Republican Party get treated differently than Democrats get treated.”

Giuliani, the Republican former mayor of New York City, has insisted that all of his activities in Ukraine were conducted on behalf of Trump. At the time, Giuliani was leading a campaign to press Ukraine for an investigation into President Joe Biden and his son, Hunter.

But some Ukrainians who were in contact with Giuliani have said in interviews that they also hoped he could help them on matters in the U.S., including arranging meetings with the U.S. attorney general and ousting the U.S. ambassador to Ukraine, Marie Yovanovitch.

The search warrants for Giuliani’s electronic devices were approved by a federal judge. 

Giuliani said Thursday that federal prosecutors told his attorney they had accessed materials from his iCloud as early as 2019.

“In the middle of the impeachment defense, they invaded, without telling me, my iCloud,” he told Tucker Carlson, without providing details.

Earlier in the day, Giuliani made his first public comments since the raid on his daily talk show on WABC Radio. On the air, he referred to prosecutors in the U.S. Attorney’s Office for the Southern District of New York, which he used to run, as unaccomplished “bullies.”

“You’re not going to stop me,” he said on the program. “And you’re not going to convict me of some phony crime.”

Trump criticized the federal investigation into Giuliani in a phone interview to Fox News Thursday saying, ‘it’s very, very unfair.”

The Associated Press and Reuters contributed to this report.