Dutch billionaire John de Mol is said to be the mysterious financier backing up Spyker's renewed bid for GM's Saab.  

A Dutch billionaire is behind Dutch sportscar maker Spyker's last-ditch bid to buy ailing Swedish carmaker Saab from US automaker General Motors, Swedish and international media sourced said.

The Dutch business daily Het Financieele Dagblad writes that the mysterious financier is 54-year-old Dutch media tycoon John de Mol. He has clear connections with Spyker as his investment company Talpa previously owned one-third of the sports-car maker.

John de Mol also has the financial muscles needed to finance the acquisition. He has created a fortune with the production company Endemol, that he owns together with Italy’s prime minister Silvio Berlusconis’s company Mediasat. His private equity fund also owns significant shares of football team Manchester United and telecommunications company Versatel. In 2005, Forbes magazine named him as one of the 500 richest people in the world.

However, Dutch newspaper De Telegraaf writes that 50-year-old Marcel Boekhoorn, who bought a 5.7 percent stake in Spyker in 2007, may be the man backing up the deal as he has been in several meetings with the Spyker management recently. Marcel Boekhoorn denies the rumor as "made up".

Spyker renewed its bid for loss-making Saab on Sunday, two days after GM broke off talks with the Dutch group and said it would begin winding down the iconic Swedish brand.

Representatives from GM and Spyker held fresh talks on Spyker's new bid on Monday in Stockholm.

Swedish press reports have suggested that one of the main reasons GM agreed to resume the talks was that the Dutch group had addressed GM's hesitations over Spyker's Russian investors.

Svenska Dagbladet reported Monday that Spyker's main investors with a 29.3 percent stake in the company, Vladimir and Alexander Antonov, were no longer behind the Dutch group's bid for Saab.

And on Tuesday, the paper said Spyker's second-biggest investor, Abu Dhabi state investment fund Mubadala Development, which owns 22.7 percent of Spyker, was not involved in the bid for Saab either.

The paper also said GM had also been concerned about letting technical know-how go to Russia.

"The risks involved with letting Saab's technical know-how go to Russia also played a role," it said.

GM has refused to comment on Spyker's renewed bid.

The Dutch group announced late Monday that it was extending its offer for Saab, initially valid until Monday at 2200 GMT, "until further notice."

Swedish media have previously reported that one of the main changes in Spyker's renewed bid is that it has said it does not need a European Investment Bank loan before the end of the year in order to pursue its bid.

GM has said it wants to sell Saab before the end of the year.