(Bloomberg) -- President Joe Biden announced he will travel to Michigan on Tuesday to support striking United Auto Workers union members, a remarkable show of solidarity during tense contract negotiations with Detroit’s Big Three automakers.

“I’ll go to Michigan to join the picket line and stand in solidarity with the men and women of the UAW as they fight for a fair share of the value they helped create,” Biden posted on X, the site formerly known as Twitter. 

The exact location and other details of the visit were not yet finalized as of Friday afternoon, according to people familiar with the matter who spoke on condition of anonymity about internal discussions regarding Biden’s travel plans.

Union leaders invited Biden earlier Friday to join the picket line. Biden’s visit will come one day before former President Donald Trump travels to Detroit to court union members and counterprogram the Sept. 27 Republican primary debate, which he has said he will not attend.

The strike has posed a political conundrum for Biden, who is counting on labor support across crucial Rust Belt swing states to help propel him to victory. 

The UAW has voiced concerns about his administration’s efforts to move the country away from gas-powered vehicles to electric cars, worried it would mean fewer jobs and worse pay. The UAW endorsed Biden in his 2020 campaign but has yet to do so for his reelection bid. 

Trump has sought to exploit that sentiment to pick off support from unionized auto workers, though union leaders have dismissed the idea the organization could endorse the former president.

Read More: GM, Stellantis Face 38 More UAW Walkouts as Ford Is Spared 

UAW President Shawn Fain said Friday the union would expand its strike against General Motors Co. and Stellantis NV, the maker of the Jeep and Chrysler brands, to 38 more facilities. It spared Ford Motor Co. from additional walk outs after union leaders said they clinched more concessions from the company. 

The sides have been far apart on key issues such as pay, benefits and terms for thousands of workers needed to staff new battery plants. An expanded strike could increase pressure on carmakers to reach a deal.

Biden has few tools to force the parties to reach an agreement, other than using his bully pulpit. Unlike last year’s freight-rail negotiation, Biden cannot legally intervene and impose a contract to get workers back on the job. 

As a result, the White House response has at times been halting. Biden announced on Sept. 15 when the UAW called the strike that he was dispatching acting Labor Secretary Julie Su and senior White House adviser Gene Sperling to Detroit in order to liaise with the union and auto executives. 

But days later, the White House said they were shelving the visit after the parties agreed it would be better if they monitored the talks remotely. Trump sought to seize on the moment, announcing his plans to visit striking workers in Michigan before Biden - who regularly bills himself as the most pro-union president in US history - scheduled a visit.


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