Milan: UniCredit SpA, Italy’s biggest bank, said its HypoVereinsbank unit is being investigated by US authorities over possible violation of economic sanctions.

HypoVereinsbank, or HVB, “has been cooperating with investigations by the New York County District Attorney’s Office, the US Department of Justice and the US Treasury Department’s Office of Foreign Assets Control involving US-sanctioned persons and companies,” Milan-based UniCredit said in an emailed statement on Monday.

UniCredit disclosed the probes in its 2011 financial statements and its latest prospectus, according to the bank, which said it was responding to a report in the Financial Times.

The Financial Times said on Monday that US authorities were probing UniCredit for possibly violating sanctions that outlaw business with Iran, which the US accuses of seeking to develop nuclear arms, a charge Iran denies.

HVB, which was acquired by the Italian bank in 2005 and now operates as UniCredit Bank AG, is carrying out a broader review of its compliance with US sanctions, according to the statement.

“The investigation and review are ongoing, and it would be inappropriate to comment further,” UniCredit said.