The German government's plans to buy stolen bank data of about 1500 tax evaders in Switzerland offered by an informer for euro 2.5 million has sparked off a major row between the two neighbours.
Toni Brunner, president of the right extreme People's Party, said if Germany buys the stolen data of account holders in Switzerland, "then it is a declaration of war on Switzerland".
If Germany gives "greater importance for cooperation with a criminal rather than with a friendly neighbour, then we must thoroughly review our relations," Brunner added.
The president of Switzerland's Christian Democratic Party Christoph Darbellay demanded a suspension of the negotiations on a double taxation agreement.
"We cannot rely on a nation which behaves in this manner," he said.
"If a constitutional state buys and deals with stolen data, it is totally unacceptable," Darbellay said.
The double taxation agreement is very crucial for Germany to get access to information on German tax evaders in that country in the future.
The Swiss government, meanwhile, offered Germany its readiness for dialogue on the stolen bank data and said it would not suspend the negotiations on a double taxation agreement. However, the Swiss government said in Bern on Wednesday that Germany's purchase of the stolen data was in violation of the "trust and good faith" in their relations.
It has already caused big strain on their relations and therefore the Swiss government will not cooperate with the German government's investigations, a government spokesman said in Bern.
A finance ministry spokesman in Berlin confirmed that the German government has decided to buy the list of tax evaders and said the amount demanded by the informer will be shared equally by the federal government and the state governments.
"We have taken a political decision to buy the data," the spokesman said. However, as a matter of rule, a final decision lies with the state responsible for that. German press reports said that the country's domestic intelligence service investigators, who received some "sample" from the list of 1500 tax evaders, estimate that the complete data offered by the informer could earn the state more than euro 100 million in tax revenue.
The German government justifies its decision to buy the data of tax evaders in Switzerland saying that it was following the precedent set in 2008 and that decision was never declared illegal by a court.
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