The government has summoned Germany's ambassador to Bern to voice anger at a German ministerial move to add Switzerland to a blacklist of tax havens.
It follows a joint press conference by the German Finance Minister Peer Steinbrück and French Budget Minister Eric Woerth on Tuesday, in which they said Switzerland deserved to be added to a list of non-transparent tax havens.
Despite a low-key response by the finance ministry to the remarks, Foreign Minister Micheline Calmy-Rey has since been charged with taking diplomatic steps through the German ambassador to Switzerland.
She will tell the ambassador that the government was surprised and unhappy with the development and did not appreciate Steinbrück's choice of words.
Switzerland is "sticking to the path of dialogue" on tax matters with the European Union, she will say.
The issue will also be addressed in a meeting between the Swiss president, Pascal Couchepin, and the head of the European Commission José-Manuel Barroso in December.
Steinbrück told a press conference in Paris that Switzerland deserved to be on the Organisation for Economic Co-operation and Development's tax haven blacklist and criticised the government for inadequate cooperation on tax matters.
Steinbrück said the Swiss system, in which tax evasion is not recognised as a criminal offence, "permitted German tax-payers to commit tax fraud".