Saab's sale to Chinese car makers Pang Da and Youngman has fallen into doubt after General Motors (GM) threatened to cut the supply of vital technology if the deal goes through.
GM said it would also stop the supply of the 9-4X SUV it makes for Saab if the sale was completed, saying it wanted to protect the best interests of GM shareholders.
GM operates a joint venture with Chinese car maker SAIC, a competitor to Pang Da and Youngman.
The protracted deal to save Saab was thought to have reached a conclusion at the end of October, when Pang Da and Youngman agreed to buy Saab for a knock-down price of 100 million (88 million).
Saab is now in discussions with Pang Da and Youngman to see whether a structure can be agreed that is acceptable to all concerned parties.