Donald Trump could well be under control of the Russian government, according to the man Trump fired as FBI director months after taking office as president.

While it was up to special counsel Robert Mueller’s investigation to determine the criminal aspects of potential collusion between Russia and the Trump campaign, the counterintelligence investigation into “whether the Russians had leverage over the president,” said Jim Comey, who served as FBI director from 2013 until 2017.

Asked whether the Russians have that leverage over Trump, Comey replied he didn’t know but “yes” it was possible.

Speaking on CNN, Comey also addressed reports and allegations that in 2016 he ordered “spying” on the Trump campaign.

Comey said that he couldn’t explain why Attorney General William “Bill” Barr calls it “spying.”

“I can’t explain it. The only explanation I can think of is he used it because the president uses it, which is really disappointing,” Comey said. “He knows better than that, and knows that the FBI conducts electronic surveillance by going to federal judges and getting warrants based on probable cause.”

The FBI operation to insert an undercover investigator as a staffer into the Trump campaign was “reasonable” to investigate a specific Trump aide, George Papadopoulos, Comey said.

“That was the guy, Papadopoulos, who was the subject of the information we got from the Australians that he had talked to the Russians,” he said.

That situation is now under investigation by the Justice Department inspector general, but Comey is certain he acted appropriately and within regulations.

“Yes. No doubt in my mind. But that doesn’t mean I’m against review of it. That’s totally fine,” Comey said.

Asked by CNN host Anderson Cooper if the inspector general might find anything inappropriate, Comey replied, “I don’t think so. At least not that I know of. But if they do, they do. And they should be transparent about it.”

Comey did admit to regrets about his handling of the investigation into Hillary Clinton’s use of a private email system as secretary of state, as many observers cite Comey’s last-minute announcement in that affair as sealing Clinton’s fate in the 2016 presidential election.

“If I can go back in time, I would find a way not to be involved at all. But if I don’t have that magic wand, I think I’d likely do it the same way. Here was my problem: I and the FBI needed the American people to trust that this wasn’t a political fix job, that this was done in a credible, fair, independent way. Secretary Clinton had engaged in conduct that was way beyond what the normal carelessness was. So how do we explain to the American people that it’s not the ordinary stuff, but it doesn’t rise to the level that you would be locked up for it? So I have to characterize the behavior in some way, not to attack her, but so that the American people understand this is the basis for their judgment,” Comey said. “It’s not criminal, but it’s not the ordinary stuff. I probably should have said ‘really sloppy’ or something, but I had to characterize it. The goal was to offer transparency to foster trust. I actually think you’ve seen it now.

“We all realize the importance of it now with the Mueller Report. The Mueller Report contains far more detail about individuals who are not charged than we ever even considered offering in the Clinton case, but it’s important for all of us to understand the basis of the decisions being made,” he added.