National Intelligence Service Director Kim Seung-kyu says his agency is closely looking into North Korea's counterfeiting.

In a Thursday briefing to the National Assembly, Kim said the government knows the North produced and distributed counterfeit currency until 1998.

An intelligence official, however, said the government made no comment on having proof that the North is still producing fake bills.

An opposition lawmaker said intelligence officials had no evidence of recent counterfeiting by Pyongyang, though they did confirm that North Korean diplomats or powerful figures distributed fake currency in 1994, 1996 and 1998.