WAYNE, Mich. (NewsNation) — United Auto Workers President Shawn Fain has threatened to expand the union’s strike against the Detroit Big Three automakers if “substantial progress” isn’t made.

The strike has garnered the attention of the top 2024 presidential candidates.

President Joe Biden had announced White House advisor Gene Sperling and acting Labor Secretary Julie Su would arrive in Michigan this week to aid in reaching a resolution with the automakers. The visit has now been canceled.

Michigan Democrats, including Rep. Rashida Tlaib, are urging Biden to show support for the union by coming to Michigan himself.

Meanwhile, a campaign advisor for former President Donald Trump confirmed he will visit Michigan next week. He plans to deliver a speech in support of the workers, coinciding with the same day as the next Republican primary debate.

In a TruthSocial post, Trump says, in part, “AUTOWORKERS, VOTE FOR TRUMP – I’LL MAKE YOU VICTORIOUS & RICH. IF YOUR ‘LEADERS’ WON’T ENDORSE ME, VOTE THEM OUT OF OFFICE, NOW.”

“They’re both very important people, so that would be great to have them on the picket line. We need all the support we can get right now,” UAW member Tiffany Kerr tells NewsNation.

Late Monday, Fain said they’re prepared to involve additional local chapters in the work stoppage if negotiations stall by 12 p.m. ET on Friday.

“We’re going to keep hitting the company where we need to, when we need to. And we’re not going to keep waiting around forever while they drag this out,” Fain said in a union news release. “I have been clear with the Big Three every step of the way. And I’m going to be crystal clear again right now.”

Fain refers to this strategy as a Stand-Up Strike, which involves target strikes at select auto factories to keep company officials guessing. So far, UAW has ordered strikes at three plants in Michigan, Ohio and Missouri in what the union referred to as the first wave of shutdowns.

The strike has the potential to escalate to an international level, potentially affecting auto workers in Canada. More than 5,000 members of Unifor, the Canadian counterpart to the UAW, were ready to strike against Ford, but those plans have been temporarily suspended for 24 hours as negotiations continue.

One of the key demands of the union is a 40% pay increase for auto workers, which remains a contentious issue in the negotiations.

Currently, full-time employees earn yearly salaries ranging from $36,000 to $80,000. In stark contrast, the CEOs of Ford, General Motors and Stellantis earn salaries that are 350 times higher, each making at least $20 million per year.

According to a professor, if the strike persists for an additional five days, it could potentially result in an economic impact exceeding $5 billion.