US justice officials are checking whether a German unit of the Italian banking group UniCredit did deals with Iran that would have violated US sanctions, Italian press reports said on Monday.
"UniCredit is included on a list of international banks under investigation for having avoided sanctions imposed by the United States against Iran," the daily Corriere della Sera said.
"The New York prosecutor, the Justice Department and the Treasury are probing UniCredit at the moment," it added.
Another newspaper, La Stampa, said US authorities were checking "certain activities by the German bank HypoVereinsbank (HVB), which was bought by UniCredit in 2005."
UniCredit said that "this affair is not new," and that information on US probes had already been published in its annual report for 2011.
If found to have skirted sanctions, the Italian bank could face stiff US fines or possibly lose its US banking license however.
The British bank Standard Chartered has settled allegations that it helped Iranian clients dodge US sanctions, by paying a fine of $340 million to a New York State financial watchdog.