Former President Trump on Monday unloaded on Florida Gov. Ron DeSantis (R), his potential presidential primary opponent, telling reporters he “probably” regrets endorsing the former congressman in a gubernatorial primary in 2018.

“He was dead as a dog; he was a dead politician. He would have been working perhaps for a law firm or doing something else,” Trump told a group of reporters traveling with him to Iowa aboard his personal plane.

The former president was asked if he regretted endorsing DeSantis, who in 2018 was facing a difficult primary race against then-Florida Agricultural Commissioner Adam Putnam for the GOP gubernatorial nomination.

“Uh, yeah, maybe, probably yeah,” Trump said, according to multiple reports. “I like people that are loyal. This guy was dead. He was dead as a doornail. Yeah, I might. I might say that. I always got along great with him when he was governor. I did a lot of good things for Florida.”

Politico reported that Trump said he ultimately decided to back DeSantis because the then-congressman had defended him against a Democratic-led impeachment effort over Trump pressuring Ukrainian President Volodymyr Zelensky to investigate the Biden family.

Trump has ratcheted up his attacks on DeSantis, who has emerged as perhaps his most formidable competitor in a potential 2024 presidential primary. Trump has declared his candidacy already, while DeSantis has shown signs he is inching closer to a campaign but has yet to announce a bid.

The former president has in recent weeks tested out a series of attacks on DeSantis, dubbing him “Ron DeSanctimonious” and accusing the governor of being ungrateful for his endorsement in 2018. 

Trump’s stop in Iowa comes days after DeSantis visited the first caucus state to speak to voters and local leaders. Over the weekend, DeSantis also traveled to Nevada, another early primary state.

DeSantis has largely ignored Trump’s attacks, and when he has responded, he has not criticized Trump by name. In one instance, the Florida governor directed critics to look at the “scoreboard,” a nod to his landslide reelection victory last November, and recently he told reporters he prefers not to spend his time “trying to smear other Republicans.”

National polls have largely shown Trump maintains a lead over DeSantis in a hypothetical primary matchup, but some polls have shown Republicans prefer the governor as their future leader.