A long-running strike at American Axle & Manufacturing (AAM) could shut a GM car plant in Lordstown, Ohio by 4 April, according to a local union official.

The plant is running out of American Axle-made brake parts for Chevrolet Cobalt vehicles and would be the first GM car plant affected by the strike

The AAM walkout threatens to deprive the factory of a brake part, which would halt work on the Cobalt, Jim Graham, president of United Auto Workers Local 1112, told the news agency.

Such a shutdown would escalate the strike's effect on GM. The 29-day walkout so far has affected production of light truck models for which GM has extra inventory, while the Cobalt car is selling relatively well, Global Insight analyst Rebecca Lindland told Bloomberg News.

"There's a lot of competition in that compact-car segment, and that could definitely be a disadvantage," Lindland said.

Lordstown employs about 2,400 people, and a shutdown may affect as many as 350 workers at related factories, Graham told the news agency. The plant probably can keep producing until 4 April, he said, adding, "Without this part we just cannot run."

GM isn't commenting on future plant closures and is assessing fallout from the American Axle strike "day by day," spokeswoman Sherrie Childers Arb told Bloomberg News.

The report said the strike at AAM, GM's largest source of axles, forced the automaker to stop or slow production at 29 plants that build pickup trucks, sport utility vehicles, vans, engines and vehicle parts.

About 3,650 UAW members at Detroit-based American Axle went on strike on 26 February over pay and benefits, the report noted.

Bloomberg News said GM's production cuts have now rippled out to other suppliers, some of which have laid off workers and halted output.

Fallout from the strike may subtract 40,000 jobs from US payrolls in March and shave 0.3% from US economic growth this quarter, Global Insight economist Brian Bethune told the news agency.