Dutch sports car maker Spyker denied on Sunday it had plans to jointly bid for General Motors' Saab with Luxembourg investment firm Genii Capital.

German WirtschaftsWoche business weekly, in abstracts of a story to be published on January 18, said the two companies, which have been trying individually to clinch a deal to buy the money-losing Swedish carmaker, had now teamed up.

Spyker Chief Executive Victor Muller, in a reply to Reuters via text message, responded No, when asked if Spyker was in contact with Genii about a joint bid for Saab or had changed its strategy.

Genii is backed by Formula 1 mogul Bernie Ecclestone.

Lars Carlstrom, who is coordinating the bid for Saab by Genii Capital and Ecclestone, told Reuters there had been some talks with Spyker's Muller last week but that he could not confirm nor deny anything related to a joint bid.

GM Europe spokesman Stephan Weinmann said GM was in talks about Saab but he declined to comment whether discussions were ongoing with one or several bidders.

GM on Monday said it would move ahead with closing Saab down. On Tuesday, it appointed two supervisors to oversee a wind-down, though it said it would continue consider several purchase proposals it has received for Saab.

The magazine's abstract said: According to WirtschaftsWoche information, Spyker Cars and Genii Capital have been in contact in order to make a last-second joint offer. It did not give other details.

Muller was still waiting for a response from GM and had no idea when it could come with a reaction to Spyker's bid, he said via telephone on Saturday.

On Tuesday, Muller said GM's decision on Saab was a matter of days not weeks. Spyker was working around the clock and was not prepared to give up on a deal to snag Saab.

(Reporting by Vera Eckert, Gilbert Kreijger and Mia Shanley in Stockholm, editing by Leslie Adler and Marguerita Choy)