GM board to reconsider Opel next month

The U.K. Department for Business, Innovation and Skills said a number of "key issues," including funding, remained under discussion. "We are working hard towards an agreement. We, like everyone else, want a speedy resolution, but on the right terms," an official said in a statement.

Magna and the Russian bank have vowed to inject 500 million euros into Opel, aiming to use it to make an aggressive push into the Russian market.

The European Commission is keeping a close eye on the transaction to ensure state aid is not misused for political purposes. Magna had won Berlin's approval by proposing to keep all four Opel plants in Germany open.

(Reporting by Maria Sheahan and Michael Shields and Kevin Krolicki, additional reporting by John McCrank in Toronto and Adrian Croft in London, editing by Matthew Lewis)