South Korea’s top nuclear envoy on Monday reaffirmed the country’s commitment to the “complete denuclearization of the Korean Peninsula” and warned of the urgency in addressing North Korea’s nuclear program during a global nonproliferation meeting at the U.N. headquarters in New York.

In a speech at the 11th Review Conference of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), Foreign Ministry director-general for foreign strategy and intelligence Jeong Yeon-doo said Pyongyang’s nuclear program is “the most pressing challenge” for the non-proliferation regime.

North Korea is “the only case” that benefitted from the NPT regime after joining in 1985,