The UN Command said it has begun talks with North Korea over the detention of a US soldier who crossed into the country last week, the US-led council said on Monday.
Pvt Travis King of the US Army ran into North Korea on July 18 during a tour of the demilitarised zone on the South Korean border.
He was to return to the US from South Korea on disciplinary grounds but joined a border tour after he went through security at an airport.
Talks between the UN Command and North Korea began through “mechanisms” established under the Korean War armistice, said Lt Gen Andrew Harrison, the UN Command's deputy commander.
He did not say when discussions took place or how North Korea responded. He also did not provide details about Pvt King's condition.
“None of us know where this is going to end, so I am remaining optimistic, but I will leave that for now,” he said.
North Korea has remained silent on the soldier.
"We have not had any substantive communications with North Korea," State Department spokesman Matthew Miller told reporters.
"We have made outreach to North Korea to let them know that we wanted to ascertain the whereabouts of Pvt King, that we wanted information about his safety, but we have not received any response to that at all."
US officials have said they do not know why Pvt King ran across the demilitarised zone, which was established in 1953 as part of the Korean Armistice Agreement.
UN Command, the multinational force created to protect South Korea, was set up around the same time.
The incident comes during a time of increased tension between Washington and Pyongyang. North Korea last week conducted ballistic missile tests hours after a US nuclear-armed submarine arrived at a South Korean port.
On Monday, the nuclear-powered USS Annapolis arrived at a port on Jeju Island in South Korea.
Washington and Seoul have increased their defensive co-operation since last year.
