UBS still seeking way out of US tax evasion probe

But the bank said it was constrained by Switzerland's strict banking secrecy laws and would under no circumstances hand customer data directly to U.S. investigators.

The bank, however, appeared to leave open the possibility that the information could be provided indirectly.

"We are still cooperating with the Swiss and the U.S. authorities to find a solution in this matter," said Serge Steiner. But he added, "A Swiss bank can never give any client data to a foreign authority. This is always a matter between Swiss authorities and foreign authorities, never between the bank and foreign authorities."

UBS could provide the customer information to Swiss authorities, who in turn can supply the data to their U.S. counterparts upon request. The procedure, known as "administrative assistance," is permissible under Swiss banking secrecy laws, though customers can appeal to Swiss courts to block the transfer of their data in the courts.

Switzerland's acting finance minister, Eveline Widmer-Schlumpf, said last month that her department would examine each case separately to determine whether administrative assistance can be provided to U.S. authorities.

UBS disclosed in May that the U.S. Justice Department is investigating whether the bank helped clients evade taxes from 2000 to 2007. The bank said at the time it was cooperating with the investigation and a separate probe into whether its bankers failed to meet registration rules set by the U.S. Securities and Exchange Commission.

The U.S. investigation has added to the bank's recent woes as it struggles to salvage its reputation in the face of massive losses linked to the subprime crisis.

UBS will hold an extraordinary general meeting in Basel on Thursday at which it will ask shareholders to approve four new candidates for the board of directors and curtail the powers of the chairman's office, which has been blamed for failing to oversee risky investment strategies.

Among those up for selection are William G. Parrett, retired chief executive officer of Deloitte Touche Tohmatsu; Bruno Gehrig, chairman of Swiss Life Holding and vice chairman of Roche Holding AG; Rainer-Marc Frey, who has held senior positions in a number of investment management companies; and Sally Bott, group human resources director of BP PLC.