DENVER (KDVR) — The United Auto Workers union strike against major automakers has expanded to a total of 41 distribution centers across the country, including two in Colorado.

“As promised, we are expanding the Stand Up Strike in response to the lack of progress in bargaining with General Motors and Stellantis,” Shawn Fain, UAW president, announced on Friday. “We will shut down parts distribution until those two companies come to their senses and come to the table with a serious offer.”

The UAW first walked out on Sept. 15 in a strike against big three automakers General Motors, Chrysler parent Stellantis and Ford. On Friday, the union expanded its strikes against GM and Stellantis.

Some 18,600 workers are now on strike across 21 states, according to the union.

UAW strike underway in Colorado

In Colorado, UAW union members are striking at two Colorado locations in the Denver metro area:

A large portion of the strikers are at 14 locations in Michigan, while more are spread among the other 20 states. In the West, workers are striking at two locations in Texas, two in California, one in Nevada and one in Oregon.

The UAW’s strategy is to keep escalating the strike if Ford, General Motors and Jeep and Ram owner Stellantis don’t move closer to the union’s contract demands, which include pay raises of 36% over four years.

The strike is a fight between the union and carmakers, but if it drags on it will reduce inventories of new cars and push prices higher – even for models made by companies that aren’t involved in the dispute, including Honda, Toyota and Tesla.

The car companies say they already pay production workers more than nonunion competitors Toyota, Honda and Tesla do, putting them at a competitive disadvantage. The Detroit Three say they can’t afford to meet the union’s demands — including a shorter work week, an end to separate and lower pay tiers for new hires, and better retirement benefits — because they must invest in the transition to electric vehicles.

The Associated Press contributed to this report.