Updated September 26, 2023 at 1:26 PM ET

President Biden walked the picket line with striking UAW workers on Tuesday at a GM facility in Wayne, Mich., donning a UAW ballcap and using a bullhorn to tell them that they had helped saved the auto industry when it went through tough times, and now deserve better pay because the industry is doing well.

"You deserve what you earned, and you've earned a hell of a lot more than you're getting paid now," Biden told the workers.

It's the first time a sitting U.S. president has been on a picket line in modern times, an extraordinary show of support for union members. UAW president Shawn Fain met Biden on the tarmac in Detroit when Air Force One landed, and walked side by side with Biden, pronouncing it a "historic moment" for workers.

"We know the president will do right by the working class," Fain said.

The strike, which began earlier this month, has ramped up pressure on General Motors, Ford and Stellantis, the country's three largest auto companies.

On Monday, Biden said he thought the UAW "gave up an incredible amount back when the automobile industry was going under."

Bill Pugliano/Getty Images

With the General Motors world headquarters in the background, United Auto Workers members attend a solidarity rally as the UAW strikes the Big Three automakers on Sept. 15 in Detroit. President Biden will join the workers in solidarity on Tuesday.

"Now that the industry is roaring back, they should participate in the benefit of that," he said. "I always support the UAW."

White House press secretary Karine Jean-Pierre said Biden's visit is to "stand in solidarity" with UAW workers. But the White House insisted Biden isn't involved in the contract negotiations.

"We believe this can be a win-win agreement for all, but we're not going to litigate the specifics of the negotiation," she said. "We never get into the specifics of negotiations ... that is something for the parties to decide on."

When the workers began their strike on Sept. 15, Biden said he would send Labor Secretary Julie Su and economic adviser Gene Sperling to Detroit. Less than a week later, the White House said the pair was staying in Washington to allow talks to move forward.

Trump will also visit Detroit

Biden isn't the only one visiting with autoworkers. His trip to Michigan comes the day before former President Donald Trump, who is also the top Republican candidate in the 2024 primary, visits the Motor City.

Trump will be skipping the second GOP primary debate on Wednesday and plans to give an address from Michigan instead.

While Biden won the UAW's endorsement in 2020, and while union workers have in the past leaned blue, the union has yet to make an endorsement in the 2024 race.

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