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FRANKFURT (AFP)--General Motors Europe said Wednesday that Italy's Fiat (F.MI), Canadian autoparts maker Magna International Inc. (MGA) and RHJ International Ltd. (RHJI.BT) are in the running to take over its Opel unit. Germany says it will choose a preferred suitor early next week.

"The three have all presented formal offers," a GM spokesman told AFP. "There were no surprises."

Fiat earlier said it made an offer for Opel and its U.K. brand Vauxhall.

The others are Magna, with support from Russian manufacturer GAZ, and RHJ International, whose main shareholder is the founder of the U.S. investment fund Ripplewood.

The German government had asked for detailed bids to determine what state aid might be forthcoming.

The DresdnerKleinwort bank, a unit of the recently part-nationalised Commerzbank, has been assigned to study the offers.

The final decision on Germany's Opel - as well as other units of GM Europe including Vauxhall and Sweden's Saab - lies with GM itself and with the U.S. government, but Berlin will sweeten any deal with loan guarantees.

"We do not have too much time," German Labor Minister Olaf Scholz told a press conference just before the deadline imposed by the German government for offers for a stake.

GM is relying on more than $15 billion dollars in emergency government loans and faces a June 1 deadline to complete major restructuring or follow car maker Chrysler into bankruptcy.

GM's chief executive Fritz Henderson said last week that a bankruptcy filing is the "more probable" outcome "given the objectives that we've set for ourselves."

The most prominent bidder is Fiat, which wants to combine GM's European, Latin American and South African operations with Chrysler to create the world's second largest carmaker, behind Japan's Toyota.

Fiat, according to unions, plans to close six units in Europe and South America and lay off 10,000 workers. The plan, codenamed Phoenix, has been roundly condemned by Opel union officials.

Bidders making a formal offer will be expected to come up with around EUR650 million, the Financial Times (FT) reported on Wednesday, and GM will give preference to cash bids.

This could be a blow to Fiat, with a spokesman telling AFP Tuesday that the firm intended to offer assets instead of cash, in a similar model to its recent deal securing a stake in Chrysler.

Fiat earlier negotiated a %20 stake in bankrupt Chrysler, in exchange for its production technology. Fiat can increase that to a controlling %5 percent share in the U.S. auto maker as long as Chrysler repays state aid.

RJH International, which has made no official comment so far, has very interesting plans for the company, Klaus Franz, the head of Opel's powerful works council, told the FT.

The fate of Opel, an industrial icon dating back to the 19th century and which directly employs around 25,000 people in Germany, has become a hot-button political issue with barely four months to go until general elections.

Chancellor Angela Merkel, up for a second term in the Sept. 27 vote, is prepared to pull out all the stops to save Opel from collapse. But her re-election hopes could be damanged if she's seen as writing a blank check on the taxpayers' account.

-Dow Jones Newswires, 201-938-5500