Opel's chairman warned that turning around the unprofitable automaker in the next few years would not be an easy road as the sale of the European carmaker to Canada's Magna (MGa.TO) drew a political storm.

A reduction of capacity is inevitable...It is important that we ensure that we have the right size for the future, Carl-Peter Forster said at the Frankfurt Motor Show.

Magna and Russian partner Sberbank (SBER03.MM) last week struck a deal to buy a majority stake of Opel from General Motors GM.UL. They plan to cut about 10,500 jobs from Opel's workforce of 50,000, half of whom work in Germany.

Some countries that are home to Opel plants have urged the European Commission to ensure that the deal with Magna did not favor German workers because of 4.5 billion euros ($6.6 billion) in promised aid from Germany.

All four of Opel's plants in Germany are to stay open, while a Belgian factory in Antwerp could close.

The Commission had said on Monday it planned to query Germany over its preference for Magna's bid for Opel over a rival offer by Belgium-based RHJ International (RHJI.BR) that called for more than 1 billion euros less in state aid.

Forster vowed that any decision on restructuring the company would not be driven by political considerations.

The European Commission will find that any final decision on restructuring Opel would be based on facts, not on politics, he said.

PAYING THE BILL

Opel presented its new Astra compact, which competes with Volkswagen's (VOWG.DE) Golf hatchback. It is among the most closely watched vehicles of the show and its best-selling model whose success would be crucial for Opel's turnaround.

Magna's co-CEO Siegfried Wolf said he did not expect the European Commission to block the takeover.

Spain's government said it would hold off deciding on state aid for Opel until it has more details on an industrial plan, though Madrid would back a European solution that guaranteed the future of Opel's plant in Zaragoza.

When you go to a restaurant, first you look at the menu, then you eat, and then you pay the bill. Here they want us to pay the bill first and we still haven't seen the menu, Industry Minister Miguel Sebastian said in a statement.

After a meeting in Berlin, the German government said countries that host Opel plants were also awaiting a detailed business plan before committing to Opel financing.

Labor representatives meanwhile sought ways to rescue the Antwerp plant from closure by shortening working hours there.

Then we could say that we build an employment bridge until there is a new product, said Opel Labor leader Klaus Franz.

Right now we don't need the capacity (in Antwerp). But if we say that the Opel brand is to be globalized, there is potential for 170,000 to 200,000 units.

Talks with Labor representatives have not yet started, but Franz said they would begin relatively soon.

(Additional reporting by Jason Webb in Madrid and Brian Rohan in Berlin; Writing by Maria Sheahan; editing by Elaine Hardcastle)

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