U.S. Representative Dean Phillips of Minnesota, a long-shot challenger to President Joe Biden for the Democratic presidential nomination, on Friday said he would not run for reelection.

The 54-year-old millionaire businessman and three-term congressman last month said he would run against Biden, seizing on the president's lackluster approval ratings and voter wariness over his age.

"It's time to pass the torch, it's time for change, and our best days are yet to come," Phillips said in a post on the X social media platform. The post linked to an interview in the Minnesota Star Tribune paper, in which he explained his move.

Phillips, who first won his seat in 2018 and won reelection in 2020 and 2022, said it would be "unproductive and uncomfortable" to run again, given his nomination bid.

Democrats, he said, were "sleepwalking into an unmitigated disaster next November," with polls showing Biden trailing Republican front runner Donald Trump in some key states.

Phillips is unlikely to affect Biden's chance of securing the party's nomination, given the incumbent's deep resources, official party support and reshaping of the party's nominating contest calendar to help fend off any early challengers.

(Reporting by David Ljunggren; Editing by Marguerita Choy)