Deutsche Bank may have done business to the tune of billions with Iran and other countries, violating U.S. sanctions. Sanctions were imposed on Iranby the international community because of its nuclear weapons program.

British bank Standard Chartered, which is said to have violated Iran sanctions, now faces payment of a $340 million settlement after New York State Superintendent of Financial Services Benjamin Lawsky exposed alleged abuses involving $250 billion in secret transactions with Iranian clients.

Four further financial institutions -- Deutsche Bank among them -- are now on the investigators’ radar. However, investigations are in the early stages and there are no concrete charges. For Deutsche Bank, the issue adds to the list of legal challenges it currently faces, which include its investment in mortgage-backed securities during the U.S. housing boom and suspected manipulation of the London interbank offered rate (Libor). According to the bank, only individual employees -- and not top management -- were involved in alleged manipulation of Libor and Euribor rates, but regulators have not yet concluded their investigations.

Further problems with U.S. authorities will only make it more difficult for Deutsche Bank’s new bosses, Jürgen Fitschen and Anshu Jain, to shake off old bank problems and focus on the present -- a major challenge in and of itself for the bank’s limping investment arm.

As such, doing business with Iran is no new subject of conflict between U.S. authorities and foreign banks. Various institutions faced with similar charges have had to pay millions in fines, among them Credit Suisse, Barclays, Lloyds, and ING.

A Deutsche Bank spokesperson stated that the bank did not wish to comment on the on-going investigations, saying only that it had taken a decision in 2007 not to undertake new business dealings with Iran, and insofar as legally possible, to pull out of existing business relations.