Former chancellor Helmut Kohl has described Greece's admission to the euro zone and Germany's own breach of EU budget rules as key factors in the crisis gripping the zone.
Two weeks before the federal election, Germany's longest- serving post-war leader surprised his Christian Democratic Union by coming out in support of its ailing coalition partner, the Free Democrats (FDP).
On Sunday he welcomed FDP leader Philip Rösler and Rainer Brüderle, its lead candidate, into his home in Ludwigshafen – with a Bild tabloid journalist.
According to Bild, Dr Kohl said the seeds for the euro crisis were planted by Gerhard Schröder – who ousted him from office after 16 years in 1998.
"The premature admission of Greece into the euro [under Schröder] was just as wrong as the weakening and breaking of the stability pact," he said.
Five years before Greece's first financial problems, Mr Schröder secured greater flexibility in interpreting EU deficit rules to allow him to stimulate his recession-hit economy.
Seven years later at the height of the euro crisis, Germany's 2005 initiative was reversed – again at Berlin's insistence.
Dr Kohl rejected the claim that he carried some blame by driving on the single currency as a political project, disregarding economic concerns. “Mistakes were made, not in the fundamental decision but its implementation,” he said.
In a dig at the new Eurosceptic Alternative for Germany, campaigning on an anti-bailout ticket, Dr Kohl added: "The idea of Europe remains correct and without alternative, above all for us Germans."