UPDATE 1-Merkel says Obama call helped seal Opel deal

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BERLIN, May 30 (Reuters) - German Chancellor Angela Merkel said on Saturday U.S. President Barack Obama helped achieve a breakthrough deal for General Motors GM.N unit Opel with a telephone call on Friday just before the final round of talks.

Merkel said she expected the final contractual details on the takeover by Canada's Magna (MGa.TO: Quote, Profile, Research) to be resolved quickly -- perhaps by the end of the holiday weekend -- even though the deal was only the start of the hard work for Opel and Magna.

"I'd like to point out that for Opel and the investor Magna the work is only now just starting and they certainly have a difficult task ahead of them," Merkel told reporters in Berlin on Saturday, several hours after the breakthrough was announced.

"Because of the special (GM/Opel) structures, the talks were a real test of trans-Atlantic relations. I spoke on the phone with the American president yesterday and we were in agreement that we had to do everything possible to come up with a good result for this complicated task.

"That conversation clearly influenced the negotiations last night," Merkel said.

A German government source said about 2,600 jobs would be eliminated in conjunction with the takeover by Magna but all four plants in Germany would remain open.

Merkel said hiving off Opel from GM was a difficult taks but added she was confident the new European-wide company based in Germany would be a boost for Europe.

"It's about creating a European company under the umbrella of Adam Opel," Merkel said. "We've got an investor with Magna and there will be no state participation even though the federal and state governments will assist with loan guarantees.