Credit Suisse has severely restricted travel to Germany by private bankers working for clients with accounts in Switzerland, due to fears that such staff could be detained by the authorities across the border.

Credit Suisse has severely restricted travel to Germany by private bankers working for clients with accounts in Switzerland, due to fears that such staff could be detained by the authorities across the border, media reports said.

The move follows the disclosure that authorities in Düsseldorf, the capital of the German state of North Rhine-Westphalia, have purchased stolen data with the names of 1,100 Credit Suisse clients in Germany with Swiss accounts. The Düsseldorf authorities said they would pursue Credit Suisse staff suspected of helping Germans hide assets and avoid paying tax.

"We have made it very clear to relationship managers they must never assist clients evading tax," the Financial Times quoted Andres Luther, a Credit Suisse official, as saying. "For some years, we have had very clear rules and regulations on travel. In the current environment, we have become very restrictive regarding travel to Germany."

Credit Suisse later told WealthBriefing that it already requires its bankers to apply for travel outside Switzerland on official business. What has changed has been that oversight of foreign travel has been tightened up, a spokesperson told this publication today. 

Credit Suisse is not the first Swiss bank to have imposed a travel restriction on its private bankers because of international rows about the use of offshore accounts. Last year, UBS brought in a temporary travel ban at a time when it was embroiled in a protracted legal case concerning alleged tax evasion in the US. However, UBS lifted its travel restrictions in December last year.

On the Credit Suisse case, reports said that the Zurich-listed bank has not had any contact from German authorities.

The willingness by the German government to purchase stolen private bank data – it bought stolen information from Liechtenstein’s LGT in the early noughties – has raised the pressure on Swiss banks. Other countries have also used, or sought to use, data that has been stolen. Last week, reports said that the UK tax authorities had move to acquire some data taken from HSBC's Swiss private banking arm.