Luxembourg's Jean-Claude Juncker said he has a preferred candidate to succeed him as head of the influential Eurogroup assembly of euro zone finance ministers but is not yet prepared to name the person.

The one who should know does know, he said in an interview with Austrian radio broadcast on Wednesday, declining to give any more details before a decision due in the next few weeks.

Citing a heavy work load and health issues, Juncker has said he will step down at mid-year from the post he has held for more than seven years.

Eurogroup officials put off last week a decision on who would be their next chairman and although Juncker has said he does not want to remain in the post, there has been talk he may be asked to stay on while the sovereign debt crisis continues.

German Finance Minister Wolfgang Schaeuble is in the running for the post.

A few names have been floated but we are not yet at a point where we could decide because I also gather the French government would prefer we make this decision only after the French presidential election, Juncker said in the interview.

The head of the Eurogroup is just one high-level European job up for grabs in what is expected to be a round of political horse trading to ensure a balance of power.

Appointments of a new European Central Bank executive board member, the head of the European Stability Mechanism (ESM) permanent euro zone bailout fund, and the London-based European Bank for Reconstruction and Development are also on the table.

(Reporting by Michael Shields; editing by Stephen Nisbet)