A key potential ally in Germany's next government is insisting Chancellor Angela Merkel's party should not keep the finance ministry because that gives her too much power.
Exploratory talks on a potential coalition of Mrs Merkel's conservatives, the pro-business Free Democrats and traditionally left-leaning Greens start this week.
Mrs Merkel's current partners, the centre-left Social Democrats, vowed to go into opposition after last month's election.
Outgoing finance minister Wolfgang Schaeuble, a member of Mrs Merkel's Christian Democratic Union, has been a powerful figure for the past eight years.
He is leaving to become parliament speaker.
The Free Democrats' leader, Christian Lindner, told Tuesday's edition of the daily Frankfurter Allgemeine Zeitung that "anything would be better than keeping the chancellery and the finance ministry in the CDU's hands ... that has not stood the test".