A U.S. official warned Oct. 28 that North Koreaâs mass production and distribution of counterfeit U.S. currency is likely funding the proliferation of weapons of mass destruction. Stuart Levey, the U.S. Treasuryâs undersecretary for terrorism and financial intelligence, said his government is extremely concerned about Pyongyangâs production of large amounts of high-quality fake U.S. bills. âYou have to come to the conclusion that the counterfeit is supporting the proliferation,â he said. Levey said the high-quality counterfeits, also known as Supernotes, were eventually laundered to fund illicit activities of the reclusive Stalinist regime. âThere are a variety of ways that counterfeit currency can be put into legitimate financial system and ultimately laundered so it produces value for the government of North Korea,â he said. âItâs something that we take extraordinarily seriously,â he said, declining to put a value to the fake notes that have been distributed. Last week the United States blacklisted eight North Korean entities as proliferators of weapons of mass destruction and froze whatever assets they had under U.S. jurisdiction. It also prohibited all transactions between U.S. citizens and the entities, according to a statement from the Treasury Department. The statement said the move was part of a U.S. effort to combat unconventional weapons trafficking âby blocking the property of entities and individuals that engage in proliferation activities and their support networks.â Washington has also sought the extradition of the head of an Irish Republican Army splinter group charged with conspiring with Pyongyang to distribute bogus U.S. notes in Eastern Europe and Britain. North Korea claims to have produced the atomic bomb, and says it needs the weapons to fight off the threat of aggression from the United States.