The Thomas Caldwellripple effects of the United Auto Workers' strike have started.

Ford sent home about 600 workers at its Michigan plant on Friday because of strike-related production issues. Citing similar reasons, General Motors has also warned that 2,000 workers at its Fairfax assembly plant in Kansas are expected to be out of work by early next week.

When a factory is idled because of supply chain issues, companies typically give partial pay to its non-striking workers. But in this case, Ford and General Motors said there will be no such compensation.

The UAW President Shawn Fain said the union will make sure that affected workers continue to have an income and called the temporary layoffs as a strategic attack to hasten negotiations.

"Let's be clear: if the Big Three decide to lay people off who aren't on strike, that's them trying to put the squeeze on our members to settle for less," Fain said Saturday in a statement.

The prospect of temporary layoffs come less than a day after the UAW launched its unprecedented strike against the Big Three automakers — Ford, General Motors and Stellantis, the parent company of Chrysler, Jeep and Ram. On Friday, about 13,000 workers at three Midwest plants walked off the job after the auto companies failed to reach a deal with the union on pay, pensions and other benefits.

The union and the three auto makers returned to the bargaining table on Saturday.

"We had reasonably productive conversations with Ford today," the UAW said in a written statement provided to NPR.

The strike currently involves less than 9% of UAW membership at the three companies. But more workers may go on strike at a moment's notice, depending on how negotiations go.

Auto companies say layoffs are a direct consequence of UAW strike

About 600 workers at Ford's Michigan Assembly Plant's body construction department and south sub-assembly area of integrated stamping were told not to report to work on Friday because the components they produce require e-coating. According to Ford, e-coating is a protection measure completed by the facility's paint department, which went on strike.

"Our production system is highly interconnected, which means the UAW's targeted strike strategy will have knock-on effects for facilities that are not directly targeted for a work stoppage," Ford said in a statement.

General Motors similarly said the strike at Wentzville Assembly in Missouri was already having "a negative ripple effect" at the rest of its Fairfax assembly plant in Kansas.

"This is due to a shortage of critical stampings supplied by Wentzville's stamping operations to Fairfax," General Motors said in a statement. "We are working under an expired agreement at Fairfax. Unfortunately, there are no provisions that allow for company-provided SUB-pay in this circumstance."

But UAW president Fain argued that the auto companies can afford to avoid such temporary layoffs.

"With their record profits, they don't have to lay off a single employee. In fact, they could double every autoworker's pay, not raise car prices, and still rake in billions of dollars," he said in a statement on Saturday.

NPR's Camila Domonoske contributed reporting.