Asked in an interview in weekly To Vima whether Juncker's successor would have to come from a triple-A country, Schaeuble said: "Member states that observe the euro zone's fiscal rules and are rewarded for this by the rating agencies and the market will possibly have better chance to promote their candidates for the post."

Schaeuble declined, however, to make further comments, saying he did "not want to talk publicly about possible candidates" or "make speculations on the issue".

Four out of the euro zone's 17 countries currently have a top credit rating: Germany, Finland, Luxembourg and the Netherlands.

Juncker's term as head of the so-called Eurogroup expires in June and he has said he does not want to keep the job.

Schaeuble reiterated in the interview that there is no guarantee that a second bailout plan for Greece, due to be approved by euro zone finance ministers next week, will work. "No-one can't rule out that Greece won't need at some point by then (2020) a third package," he told To Vima.

He also dismissed any notions that Germany was using the euro zone crisis to dominate Europe.

"Drawing the conclusion that we want to dominate Europe is really, just foolish", he said. "I can assure you that Germany has neither the intention nor the power to impose such a dominance".

(Reporting by Harry Papachristou; Editing by Andrew Heavens)

• A Permanent Economic Emergency