The United Auto Workers union escalated its strike against the big three US automakers on Friday as the industrial action entered its third week.

In a livestream update on the strike on Friday, the UAW president, Shawn Fain, said another 7,000 workers would be joining the action. About 25,000 workers are now on strike.

Fain said: “We are fed up with corporate greed and we are fed up with corporate excess. We are fed up with breaking our bodies for companies that take more and more and give less and less.”

Fain said bargaining with Ford and General Motors had not made meaningful progress in the past week, adding Ford’s Chicago assembly plant and a GM plant in Lansing, Michigan, to the strike. Action at Stellantis was not escalated this week due to progress made in talks.

The strike has become a hot-button issue in political circles with Joe Biden and Donald Trump visiting Michigan this week to address autoworkers.

“This strike is absolutely about the worker and listening to the worker,” Haley Stevens, a Democrat representing Michigan’s 11th congressional district, told the Guardian. “This strike has opened up new channels to hear from workers in ways that we haven’t seen in a very long time in the country.”

Stevens served as chief of staff to the US Auto Rescue Task Force under the Obama administration and has appeared on the strike picket lines in support of autoworkers. She recently reintroduced a bill to protect union autoworkers in Congress.

She said the concessions autoworkers made to help the auto industry recover from the 2008 economic recession have not been returned. She also praised the work auto employees did to get the industry through the Covid-19 pandemic.

“Now is the time to recognize that work, and their fair share of the profit, and ensure that anyone who works at the automakers is treated fairly, and dealt in to the profits and to the transition that’s under way,” Stevens added.

Shaun Collier, a Stellantis assembly worker in Sterling Heights, Michigan, said: “The big three have been making record profits, giving themselves increases, while us UAW members are the ones doing all of the work, putting wear and tear on our bodies, missing our kids’ extracurricular activities because we are forced to be here to build a product we can’t even afford.

“All we want is a livable wage, a work-life balance, and job security.”

Biden joined the UAW picket line in Michigan on Tuesday, the first sitting president ever to do so.

“The fact of the matter is you guys, the UAW … you saved the automobile industry back in 2008 and before. You made a lot of sacrifices, gave up a lot. The companies were in trouble. Now they are doing incredibly well, and guess what? You should be doing incredibly well too,” Biden said.

Trump held a rally at a non-union auto parts plant outside of Detroit on Wednesday, coinciding with the Republican presidential primary debate.