General Motors said on Tuesday it would lay off an undetermined number of workers at a Detroit-area assembly plant in mid-March as it slows production of some of its luxury sedans, Reuters reported.

According to Reuters, GM said it would slow the production line speed to cut output of Cadillac DeVille, Cadillac Seville and Buick LeSabre sedans at the Detroit-Hamtramck assembly plant.

"There will be some layoffs. The actual number has not yet been determined," GM spokesman Dan Flores told Reuters while declining to comment on a weekend report that the production cut would likely result in the layoff of 500 to 600 of the plant's approximately 3,400 hourly workers.

Reuters said US sales for all three of the large sedans fell last year, with Seville falling 15%, DeVille by 11% and LeSabre by 6.5 %. Under the UAW contract, laid-off hourly workers with at least one year's experience receive about 95% of their take-home pay, Reuters noted.