General Motors will cut more than a quarter of its North American manufacturing jobs and slash vehicle numbers as the firm fights for survival.
It will close nine North American plants and axe 30,000 jobs - 5,000 more job cuts than the 25,000 that the company had previously indicated.
It is aimed at returning the world's biggest carmaker to profit after absorbing nearly £2.3 billion in losses so far this year.
Chairman and chief executive Rick Wagoner said: "The decisions were very difficult to reach because of their impact on our employees and the communities where we live and work.
"But these actions are necessary for GM to get its costs in line with our major global competitors. In short, they are an essential part of our plan to return our North American operations to profitability as soon as possible."
Mr Wagoner said the company had informed the leadership of the United Auto Workers union of the moves, calling it "tough medicine for us and tough medicine for everyone involved".
It will cut the number of vehicles GM is able to build in North America by about one million a year by the end of 2008, as it realigns production with demand.
GM said the assembly plants that will close are in Oklahoma City; Lansing, Michigan; Spring Hill, Tennessee; Doraville, Georgia; and Ontario, Canada. A shift also will be removed at a plant in Moraine, Ohio.
An engine facility in Flint, Michigan, will close, along with a separate powertrain facility in Ontario and metal centres in Lansing and Pittsburgh.
Mr Wagoner said GM would also close three service and parts operations facilities. They are in Ypsilanti, Michigan, and Portland, Oregon.