A decision on the search for a new investor for German carmaker Opel will be made next week, dpa cited Economics Minister Karl-Theodor zu Guttenberg as saying today. Three firms have submitted bids to take over the European operation of troubled US carmaker General Motors (GM), among them Canadian-Austrian car parts and assembly group Magna. Zu Guttenberg said Magna had presented "an interesting concept," but one that "raised questions." He said the government had to weigh the risks involved if asked to provide state credits to finance new investments in Opel. The other firms seeking to take over Opel are carmaker Fiat of Italy and US-based private-equity group Ripplewood. The German government is expected to participate in a bail-out. The government discussed the bids on Friday with the leaders of four federal states where Opel has plants. One of the leaders, Hesse Premier Roland Koch, said the states' first choice was Magna, but North Rhine-Westphalia Premier Juergen Ruetters said he was not happy with Magna's plans. Canada-based Magna, which has extensive operations in Austria, filed its proposal in conjunction with Russia automotive group GAZ and Russia's Sberbank. Magna spokesman Daniel Witzani said the plan envisaged GM and Magna's Russian partner each taking a 35 per cent stake, with Magna holding 20 per cent and Opel employees 10 per cent of the new company. Witzani, speaking in Vienna, said the company would not close any of Opel's plants in Germany if the deal went through. Opel employs about 25,000 people in Germany. Fiat has said it expects 10,000 jobs to be axed if its bid is accepted. Magna did not give an exact figure but information obtained by the German Press Agency dpa suggested 2,600 jobs would go, the bulk of them in North Rhine-Westphalia. Magna said it wants the German government to make available 4-5 billion euros in state guarantees to support the new operation. The final decision on the future of GM's European subsidiary will be reached by GM and the US government, but Germany has a stake in the decision as any outcome is likely to rely on the German state guarantees. Meanwhile, GM must present the US government with a viable strategy for survival by May 29. A German delegation is on standby to travel to Washington for negotiations over the weekend.