(Bloomberg) -- Billionaire investor Bill Ackman said President Joe Biden risks tarnishing his political reputation by seeking a second term and that he’s intrigued by Representative Dean Phillips’s primary challenge for the Democratic nomination.

“I think Biden’s done a lot of good things. But I think his legacy will not be a good one if he is the nominee,” Ackman said in an interview with Bloomberg Television. “I do think the right thing for Biden to do is to step aside, and to say he’s not going to run, and create the opportunity for some competition.”

The Pershing Square Capital Management founder said he recently met with Phillips and was “impressed” by the 54-year-old congressman who represents a swing district in Minnesota. Phillips launched a longshot presidential campaign last month, saying it was time for a new generation of leaders.

“You need to be at your intellectual best. And I don’t think Biden is there,” Ackman, 57, said in an upcoming episode of The David Rubenstein Show: Peer-to-Peer Conversations that will debut Dec. 6 at 9 p.m. New York time on Bloomberg Television. “I don’t say that, you know, with any derision of the president,” he continued. “But I think he’s clearly past his physical and cognitive peak.”

Polls show voters hold serious doubts about Biden’s fitness to serve another four years. Biden, who turned 81 earlier this month, is already the oldest US president in history.

While Ackman has flirted with political candidates from across the political spectrum, Biden will need to make sure that he assuages any concerns over his age shared by more traditional deep-pocketed Democratic donors. Their support and financial backing will be essential in Biden’s bid to return to the White House.

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Biden’s allies and people who interact with him say the focus on his age and health is unfair and that the president is healthy enough to serve. They point to his work schedule as well as exercise routines prescribed by the White House physician. Biden himself has made light of his age at recent events.

Ackman, who has traditionally donated to Democrats, said he is “much more open to Republican candidates” than reelecting Biden. The hedge fund manager said he is supportive of former South Carolina Governor Nikki Haley and ex-New Jersey Governor Chris Christie, two Republicans who are vying with former President Donald Trump for the nomination. He also donated to entrepreneur Vivek Ramaswamy, but said his policies fell short of expectations.

“He’s just been a little too far off to the right,” Ackman said. “I’ve been disappointed a bit with his geopolitics.”

Ackman, best known for being an activist investor and taking controversial positions on market conditions, is worth about $2.3 billion, according to the Bloomberg Billionaires Index. 

He said he’s potentially open to running for political office himself under the right conditions.

“If the country wanted me at some point, you know, I would be open to it,” Ackman said. “It’s something where the country would have to ask me as opposed to me putting myself out there.”

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