The U.S. crackdown against offshore tax evasion has led to charges against UBS AG, the largest Swiss bank; at least 21 foreign bankers, advisers and attorneys; and at least 36 U.S. taxpayers.

UBS, which isn't one of the 11 banks now under scrutiny, avoided prosecution in 2009 by paying $780 million, admitting it fostered tax evasion and handing over details on 250 secret accounts. It later disclosed another 4,450 accounts.

UBS made 10.75 billion francs ($12.1 billion) in revenue in the U.S. in 2010, or 34 percent of the group's total. Credit Suisse made 12.84 billion francs in revenue in the Americas in 2010, or 41 percent of the total. HSBC's Swiss private bank and Julius Baer declined to disclose information on revenue from U.S. clients. A spokesman for HSBC in Geneva declined to comment on the settlement talks.

Credit Suisse rose 3.3 percent to 24.64 Swiss francs in Zurich. Baer rose 1.3 percent to 35.14 francs. Basler Kantonalbank was unchanged and Liechtensteinische Landesbank fell 3.2 percent.

Urs Rohner, chairman of Credit Suisse, last month told newspaper NZZ am Sonntag that the bank has transferred statistical data sought by the U.S. Marc Dosch, a spokesman for the Zurich-based bank, declined to comment further.

Basler Kantonalbank spokesman Michael Buess said it also gave such data to the U.S.

Wegelin & Co. spokeswoman Albena Bjoerck said it will show "Swiss and U.S. authorities that the bank has not breached either Swiss or U.S. law." The bank is cooperating with authorities "within the scope of Swiss law."

After a U.S. indictment of two Julius Baer bankers this month, the bank said it "is one of a number of Swiss financial institutions supporting the ongoing tax negotiations between the U.S. and Switzerland" and is cooperating with the U.S. probe. Spokesman Martin Somogyi declined to comment further.

Youval Dichovski, Zurich-based head of internal audit at Bank Leumi Switzerland Ltd., said the bank is cooperating.

Bank Hapoalim Switzerland is complying with its legal and regulatory duties in cooperating with Swiss authorities, said Chief Executive Officer Michael Warszawski. He said the bank "has only a limited number of American clients whose holdings with the bank are very small." The bank, he said, "is not aware of any violations of U.S. law by the bank or its employees."