German Finance Minister Peer Steinbrück has hit back at Swiss comments comparing him to a Nazi and said he had received threatening letters from the alpine country.
The growing war of words between Switzerland and Germany over banking secrecy intensified on Wednesday when a Swiss politician said Steinbrück reminded him of the Nazis.
"I'm getting threatening letters from Switzerland and am being bad-mouthed as a Nazi stooge," Steinbrück told the German newspaper Süddeutsche Zeitung on Thursday.
"This is completely out of proportion and unacceptable," he added, saying the dispute arose because of a realisation in Switzerland that the country was violating international norms.
On Wednesday Swiss parliamentarian Thomas Müller of the centre-right Christian Democratic Party said Steinbrück reminded him of the "generation of Germans who marched through the streets in leather coats, boots and armbands".
Müller was speaking during a heated debate in the country's parliament after Switzerland, the world's biggest offshore centre, offered to relax bank secrecy in the face of a global crackdown on tax havens led by Germany.
Steinbrück, who angered Switzerland last year by calling for a "carrot and stick" approach on the tax issue, prompted new outrage on Saturday when he compared Germany's southern neighbour to "Indians" running scared from the cavalry.
It was not the first time Germans have been compared to Nazis for campaigning against tax havens. In September Liechtenstein's Prince Hans-Adam II dubbed Germany a "Fourth Reich" after Berlin launched a probe into rich citizens who parked savings in the principality.