Israel's largest bank says the cost of settling a U.S. tax evasion probe could be "significantly higher" than previously anticipated.

Bank Hapoalim is being investigated by the Justice Department and New York state over allegations that it helped American clients evade taxes.

In a report to the Tel Aviv Stock Exchange Tuesday, the bank said it is in talks with American authorities over the terms of a potential settlement. It said certain "findings" may have "an adverse effect" without elaborating. The bank already has set aside nearly $200 million for a potential settlement.

Israel's Bank Leumi allegedly helped U.S. customers evade U.S. taxes from 2002-2010, and reached a settlement with the Justice Department in 2014 to pay $400 million to the U.S. government.