UAW president Shawn Fain announced the union was expanding its "stand up" strikes at 12 p.m. ET Friday, but only against GM and Stellantis, after the union said “real progress” was made with Ford in negotiations this week.

Workers at parts distribution facilities for GM and Stellantis will “stand up” and strike at 38 locations, across 20 states, Fain said. “Our stand up strategy is designed to do one thing, win record contracts,” he said. With stand up strikes, instead of striking at all plants all at once for a certain automaker, select local UAW chapters will be called on to “stand up” and walk out at targeted facilities, giving what the UAW says is "maximum leverage and maximum flexibility" in negotiations with the automakers.

While negotiations at Stellantis and GM have not progressed as the UAW would like, Fain revealed the union had reached a number of concessions with Ford — covering issues including the reinstatement of a COLA (cost-of-living adjustment formula), right to strike at plants over closures, an enhanced profit sharing formula, and immediate conversion of temporary employees, among other things.

“This last week we’ve made some real progress at Ford,“ Fain said. “We do want to recognize that Ford is serious at reaching a deal.”

“Stellantis and GM are going to need some pushing,” Fain added.

Ford said in a statement released shortly after Fain’s comments that it is “working diligently with the UAW to reach a deal that rewards our workforce and enables Ford to invest in a vibrant and growing future," and even though it is making progress in some areas, the two sides "still have significant gaps to close on the key economic issues."

Fain noted the decision to strike at GM and Stellantis parts and distribution plants is because workers there were “stuck at lower wage scale” than workers at other facilities.

Finally, Fain maintained that the current stand up strikes that began last Friday are still in effect until further notice. The UAW is currently striking at GM's Wentzville, Mo., plant, Stellantis's Toledo Assembly plant in Ohio, and Ford's Michigan Assembly plant in Wayne, Mich.

The UAW expanding its strikes was expected by those in the industry, though the exclusion of Ford is noteworthy. This comes as the rancor rises between the union and the Big Three.

Earlier this week leaked texts from a member of the UAW’s communications team hinted at what the UAW’s plan would be for its stand-up strikes. In the texts, the UAW executive said the intent of the union was to keep the Big Three “wounded for months” with extended strikes, and the union intended to pit the Big Three against each other by negotiating against competing offers.

While UAW negotiating tactics noted in the leaks should not come as a surprise to the automakers, companies condemned the tactics nonetheless.

“It’s now clear that the UAW leadership has always intended to cause months-long disruption, regardless of the harm it causes to its members and their communities. The leaked information calls into question who is actually in charge of UAW strategy and shows a callous disregard for the seriousness of what is at stake,” GM said in a statement.

Ford called the tactics “disappointing,” but said it would continue to bargain in “good faith” to reach an agreement.

Pras Subramanian is a reporter for Yahoo Finance. You can follow him on Twitter and on Instagram.

Click here for the latest stock market news and in-depth analysis, including events that move stocks

Read the latest financial and business news from Yahoo Finance