GM CEO Fritz Henderson said last week that although talks are underway with Canadian parts maker Magna to purchase Opel, the American automaker is open to other offers for its European operations.
"We're just negotiating," said Henderson. "We don't have an exclusivity agreement, so we are open to discussion with others.
"We are spending a lot of time with Magna trying to negotiate a more definitive agreement."
The German government chose Magna's offer over several others, including one from Italy's Fiat. Still, officials echoed Henderson's statement last week, as German Economy Minister Karl-Theodor zu Guttenberg confirmed talks with other suitors are still underway.
"We are still in contact with other investors," Guttenberg said at a press conference.
"BAIC (Beijing Automotive Industry Holding Corp), for example...and others that I will not speak about here."
Italy's Prime Minister Silvio Berlusconi said Fiat's proposal is still under consideration after criticism that the Italian government wasn't doing enough to support Fiat's bid for Opel.
"We are waiting for the situation to clarify itself," he told reporters after talking with Fiat CEO Sergio Marchionne.
Roland Berger, a German consultant who was hired by GM to help it find a buyer for Opel--and who happens to sit on Fiat's board of directors--says Fiat's offer could still be in the running despite the talks with Magna.
"Fiat's industrial plan is the best and most attractive because it would have created a global group with pan-European roots that would be very strong," he said. "This is not the last word."