The Goteborgs Posten daily reported on its website that a source within Ford said BMW has been studying a possible purchase of Volvo.
The Financial Times also reported last Friday BMW was in informal talks to buy Volvo.
"We cannot comment on speculation, this is a question for our owner," said a spokeswoman for Volvo cars.
Ford bought Volvo in 1999 and it is now part of the U.S. company's Premier Automotive Group, including Jaguar and Land Rover.
Ford does not disclose results for its individual brands, but taken together its luxury line-up lost $327 million in 2006.
Merrill Lynch has said Ford could raise over $9 billion by selling the remaining luxury car brands.
Volvo Cars Chief Executive Fredrik Arp told Reuters in March that Ford was committed to keeping the Swedish car maker.