U.S. Special Representative for North Korea, Sung Kim and Noh Kyu-duk, South Korea's Special Representative for Korean Peninsula Peace and Security Affairs, attend a briefing after their meeting at a hotel in Seoul, South Korea October 24, 2021. Ahn Young-joon/Pool via REUTERS

SEOUL, Oct 24 (Reuters) - North Korea's recent ballistic missile tests were "concerning and counterproductive" for efforts to reduce tensions, and Pyongyang should instead engage in talks, the U.S. envoy for North Korea said on Sunday.