The U.S. Department of the Treasury has announced sanctions against three North Korean party officials over their alleged involvement in the country's illegal weapons development program.

The department said in a statement on Thursday that its Office of Foreign Assets Control(OFAC) imposed sanctions on three individuals for their roles as officials of the North's Workers' Party.

The department said the blacklisted individuals, Jon Il-ho, Yu Jin and Kim Su-gil, directly led North Korean organizations that are linked to the development of weapons of mass destruction(WMD).

Under Secretary of the Treasury for Terrorism and Financial Intelligence Brian Nelson said that the department is taking action in close trilateral coordination with South Korea and Japan against officials who have had leading roles in the North's unlawful WMD and ballistic missile programs.

The U.S. blacklisted the Workers' Party in 2016 and the three individuals are all members of the party's Central Committee. The trio are also under European Union sanctions.