The U.S. Internal Revenue Service continues to ramp up its pressure on Swiss banks as part of its widespread investigation into Americans who have dodged their taxes with the help of international financial institutions. This time around three Israeli banks with branches in Switzerland are also being targeted. The U.S. tax authority announced over the weekend that it expects ten banks, including Bank Hapoalim, Bank Leumi and Mizrahi-Tefahot, to turn over more specific data about clients it suspects of tax evasion by Sept. 23. The U.S. is in the process of drafting legal documents to force the banks to disclose the identities of American clients who had evaded taxes, Reuters reported. Swiss Foreign Minister Micheline Calmy Rey said on Wednesday that Switzerland had given the U.S. statistical data about U.S. taxpayers, but had not handed over any bank client data, according to Reuters. Swiss law, which protects banking secrecy, allows banks to hand over statistical data. The U.S. has recently increased efforts to combat tax evasion in the global banking system and it appears, for the moment, that the Swiss bank tradition of preserving client anonymity is standing up to U.S. pressure. "We are talking about a request for statistical data," a senior banking system official said on Saturday. "We are not talking about clients' names and it is important that the public knows that." A source at Bank Leumi responded on Saturday, "There was indeed a request made by the Swiss authorities to ten Swiss banks, including Leumi, to obtain general statistical information. As it appears now, this statistical information was intended for use as a base for a comprehensive agreement between the banking sector in Switzerland and the American and Swiss authorities. Bank Leumi Switzerland cooperated with the request, according to Swiss law and its legal counsel." Bank Hapoalim responded that, "The bank [in Israel] cannot comment on matters relating to Bank Hapoalim Switzerland because it is a Swiss bank that acts according to Swiss law." Mizrahi-Tefahot did not comment as of press time.