The future of MG Rover remains uncertain despite the announcement of a multi-million pound buyout deal last week.
On Friday, administrators PricewaterhouseCoopers said it had agreed to sell the collapsed carmaker to China's Nanjing Automobile for an estimated £50 million.
But rival bidder and corporate trouble-shooter David James says he plans to submit a fresh offer after his first two were turned down.
SAIC, also from China, says it may launch a legal challenge to the Nanjing deal.
Nanjing has pledged to create a design, engineering and manufacturing facility in the United Kingdom. The Chinese firm said it will "seriously consider" Longbridge as the location for its manufacturing site.
But SAIC, which lost out to its rival, said at the weekend it was considering all options - including the possibility of legal action. A spokesman said the company was disappointed at losing out and insisted its bid was superior to that of Nanjing's.
SAIC said: "The process has not been handled fairly or in the best interests of creditors and employees. Our offer gave a firm guarantee of substantial employment at Longbridge. It was at least equal and probably superior to Nanjing's.