Glyn Davies, U.S. special envoy for North Korean policy, arrived Thursday in Seoul for a three-day visit to discuss security issues on the Korean Peninsula.
He was quoted by South Korea's official Yonhap News Agency as saying the focus of his talks with officials in Seoul would be on the North Korean nuclear issue.
A failed rocket launch by Pyongyang in April sparked concerns the country was preparing for a nuclear test. Similar launches in 2006 and 2009 coincided with the country's first two tests of nuclear devices.
Davies said any act of provocation from the North Koreans ahead of Nov. 6 presidential elections in the United State would be "very counterproductive."
"One of the things we will talk about here in Seoul is how to react should North Korea decide to engage in the acts of provocation," he was quoted as saying. "But I'm hopeful that it understands to engage in such an act will be a mistake."