The Treasure Department recently added 10 Iranian shipping companies and a shipping executive to a black list that freezes any assets they may have US jurisdictions and bars Americans from doing business with them.

The companies are affiliates of Iran's state-owned shipping line, IRISIL, which is already subject to US sanctions for activity related to Iran's missile programs and transporting military cargoes.

The executive and the companies, including a joint venture between IRISIL and an Indian shipping company known as Irano Hind, are all based in Malta. Treasury alleges that they have all tried to help IRISIL avoid previous sanctions by serving as front operations.

Malta said Thursday it supports US and European efforts to crack down on Iranian companies operating from the tiny Mediterranean country.

The Foreign Ministry said that while it will not physically shut them down it will apply international sanctions that will bar them from entering into new deals or contracts.