General Motors has substantial doubt about its ability to continue as a going concern if it fails to stem its losses and generate cash, and it may be forced to file for bankruptcy, the automaker said on Thursday.

GM has requested up to $30 billion of government loans to survive the industry downturn.

Shares of GM were down nearly 7 percent at $2.05 in light trading before the market opened.

(Reporting by Franklin Paul; Editing by Lisa Von Ahn)