An informant has offered to sell the German government the data of 1,500 possible tax evaders with bank accounts in Switzerland, a respected German daily reported yesterday, without identifying its sources.

The informant is asking for €2.5m for the confidential data, which tax investigators believe could rake in €100m for German state coffers, the Frankfurter Allgemeine Zeitung wrote.

German finance minister Wolfgang Schaeuble is considering whether to go ahead with the transaction, the paper added. A ministry spokesman declined to comment on the report.

In 2008, Germany purchased data on tax evaders from an informant about clients of a Liechtenstein bank.

The case snared former Deutsche Post chief Klaus Zumwinkel, who was given a suspended jail term last year for evading nearly €1m in taxes using a Liechtenstein trust.

Schaeuble's predecessor, Peer Steinbrueck, clashed repeatedly with Germany's neighbours Switzerland, Liechtenstein and Luxembourg over bank secrecy, accusing them of serving as havens for German tax evaders. The three countries have taken steps in the last year to improve transparency on taxes.