Swiss ambassador to Berlin Tim Guldimann defended a tax deal with Germany on German public television last night, saying banking secrecy has surely been abused for tax evasion, but evasion is not the core principle of the system.

“It doesn’t play a role. The problem is that you are accusing the Swiss financial center to have helped clients to evade taxes. It has happened before, but today the Swiss government says: only taxed money in Switzerland,” Guldimann said on broadcaster ARD. ”We want an agreement with Germany to solve this issue once and for all, and to rid the world of this problem.”

Norbert Walter-Borjans, the finance minister of the German state of North Rhein-Westphalia, meanwhile, said the tax deal was dead.

“The deal on the table right now keeps the interests of Swiss banks and tax dodgers, and for us it is a worse solution than we had before, so the deal doesn’t work,” he said.

Walter-Borjans was introduced on the program as a “boogie man” for Switzerland, and recently said he would consider continuing to buy CDs of stolen Swiss bank data regardless of a tax deal.