The U.S. is reportedly hoping the European Union (EU) will join in sanctions against North Korea's primary foreign exchange bank.

A U.S. State Department official said on condition of anonymity Monday that a decision to sanction the Foreign Trade Bank is a very important issue and the U.S. wants the EU to consider taking part.

The official said, however, there could be some complications in the EU joining the sanctions, as some EU countries with embassies in the North deal with the bank for embassy operations.

Though the bank does not fall under UN Security Council sanctions, the U.S. independently imposed sanctions on the Foreign Trade Bank as it believes the bank helps finance North Korea's ballistic missile program.