Jean-Claude Juncker, the Luxembourg premier considered a founding father of the euro, was asked to stay on as head of the eurozone finance ministers group, an EU source said on Tuesday. "The mandate is for two and a half years but he will only serve for part of that," another EU source told AFP. Juncker, who has held the post since 2005, was due to step down in exactly one week, on July 17. He has himself suggested remaining in the post for a further six months. His renomination was agreed by his peers during almost nine hours of talks Monday that lasted well after midnight. Finding a successor has been tricky, with the most likely new candidate, German Finance Minister Wolfgang Schaeuble, running into French opposition. Juncker favoured handing over the post but agreed under French pressure to remain another six months on condition that the head of the Luxembourg central bank, Yves Mersch, should take a vacant board seat at the European Central Bank. The Eurogroup agreed to nominate Mersch to the ECB board during the talks, with the formal adoption to be agreed later Tuesday when all 27 European Union finance ministers meet. Mersch, 62, has been head of the Luxembourg central bank since 1998 and will replace Spain's Manuel Gonzalez Paramo, who stepped down from the ECB post in May.