Many US clients of UBS who are facing investigation for tax evasion are coming forward to authorities in a voluntary disclosure programme, a US lawyer said, according to Reuters yesterday.

William Sharp was quoted saying that a significant number of these UBS customers under scrutiny by US tax authorities were wealthy Jewish individuals and families, many of them descendants of survivors of the Nazi Holocaust who had set up accounts in Switzerland to protect their assets.

The US government is suing the world’s biggest wealth manager to retrieve thousands of names of US clients who put money in offshore accounts.

UBS has already paid a $780 million fine to settle criminal charges that it helped US tax evaders; it has also moved to stop providing offshore banking to US clients. However, the Zurich-listed bank is resisting handing over details on up to 52,000 clients to US authorities.

The clash between UBS and the US tax authorities has been a factor in encouraging rising pressure by large industrialised countries against tax havens. In April, the Group of 20 nations, meeting in London, vowed to step up pressure on offshore financial centres such as Switzerland, Liechtenstein, Monaco and The Cayman Islands.

Opponents of tax havens argue they encourage citizens to evade taxes imposed by democratically elected governments, forcing people who cannot move money offshore to pay more money. However, defenders of tax havens say these jurisdictions encourage governments, operating in a world of mobile capital, to keep taxes as low as possible. They also argue that banking secrecy is an important protection for groups fleeing oppression or rapacious governments.