By David Shepardson and Joseph White

(Reuters) -The United Auto Workers union said it would announce on Friday more plants to strike if no serious progress was made in talks with Ford, General Motors and Chrysler-parent Stellantis, adding to pressure on the Detroit Three automakers.

Ford <F.N> also faces a total strike at its smaller Canadian operations if no agreement is reached on Monday evening with the union representing about 5,600 Canadian auto workers, just days after workers at one of its U.S. plants walked out.

The UAW last week launched a targeted strike against Ford, GM and Stellantis, targeting one U.S. assembly plant at each company.

“We’re not going to keep waiting around forever while they drag this out,” UAW President Shawn Fain said in a video message late on Monday setting the new deadline after complaining about a lack of progress in recent talks. “We’re not messing around.”

Canadian union Unifor, whose contract with Ford expires at 11:59 EDT on Monday (0359 GMT on Tuesday), said there was still no deal just hours before the deadline.

Unifor National President Lana Payne said in a video posted on the union’s website that Ford needed to do more to meet members’ expectations and demands.

“If there is a strike, this will be a total strike,” she said. “Every single one of Unifor’s 5,600 members at Ford in Canada will be on picket lines.”

Ford has two engine plants in Canada that build V-8 motors for F-series and Super Duty pickups assembled in the United States. It also has an assembly plant in Ontario.

A walkout by Canadian workers that shut down those engine plants could cripple U.S. production of Ford’s most profitable vehicles, even if the UAW decides not to order walkouts at truck plants in Kentucky; Dearborn, Michigan; and Kansas City, Missouri.

“Ours is a small but highly consequential footprint for Ford operations in North America and this is our leverage, and we will use it,” Payne said.

US NEGOTIATIONS CONTINUE

Talks between the UAW and the Detroit automakers continued on Monday as a strike by auto workers over pay dragged on for a fourth day with little sign of progress toward a deal. Some 12,700 workers are striking at the three U.S. plants, including 3,300 at Ford’s Wayne, Michigan assembly plant.

Union negotiators and representatives of GM, Ford and Stellantis held talks over the weekend in an attempt to end one of the most ambitious U.S. industrial labor actions in decades. On Monday, the UAW held talks with Stellantis though no deal was reached. It had scheduled a new round of talks with Ford for late afternoon.

Fain told NPR on Monday there were “minimal conversations over the weekend so the ball is in their court …. We have a long way to go.”

Treasury Secretary Janet Yellen said it was premature to forecast the strike’s impact on the economy, which would depend on how long the action lasted and what was affected.

The strikes have halted production at plants in Michigan, Ohio and Missouri that produce the Ford Bronco, Jeep Wrangler and Chevrolet Colorado, alongside other popular models.

Ford on Friday furloughed 600 workers who are not on strike at the Michigan Bronco plant because of the impact of the work stoppage. GM said it expected to halt operations at its Kansas car plant early this week because of the strike at its nearby Missouri plant, affecting 2,000 workers.

Analysts expect plants that build more profitable pickup trucks like Ford’s F-150, GM’s Chevy Silverado and Stellantis’s Ram to be the next strike targets if the walkout continues.

The union and companies are at loggerheads over pay and benefits for workers. The three automakers have proposed 20% raises over the 4-1/2-year term of their proposed deals, though that is only half of what the UAW is demanding through 2027. The UAW at one point during the talks offered to lower its demand to 36%.

Besides higher wages, the UAW is also demanding shorter work weeks, restoration of defined benefit pensions and stronger job security as automakers make the shift to electric vehicles.

Separately, former President Donald Trump plans to skip the second Republican presidential debate and make a speech in Detroit on Sept. 27 to autoworkers and others discussing vehicle issues, an aide said.

(Reporting by David Shepardson and Ben Klayman; Additional reporting by Doina Chiacu and Jeff Mason; Editing by Alexander Smith, Richard Chang and Jamie Freed)

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