Speaking to reporters after meeting with his South Korean counterpart in Seoul, Special Representative Sung Kim said the United States is committed to exploring "sustained and substantive diplomacy" with North Korea.
"Our goal remains the complete denuclearization of the Korean peninsula," Kim said. "That’s why Pyongyang’s recent ballistic missile test, one of several in the past six weeks, is concerning and counterproductive to making progress toward a lasting peace on the Korean peninsula."
Pyongyang so far has rejected U.S. overtures, accusing Washington and Seoul of talking diplomacy while ratcheting up tensions with their own military activities.
On Thursday, the North said the United States was overreacting to a submarine-launched ballistic missile test that it called self-defensive, and questioned the sincerity of Washington's offers of talks, warning of consequences.
That launch violated multiple United Nations Security Council resolutions and poses a threat to North Korea's neighbors and the international community, Kim said.