The US State Department expressed frustration when North Korea announced a cut of contact with South Korea, calling for the two peninsula to cooperate.

"The United States has always supported progress in inter-Korean relations and we are disappointed with the recent actions of North Korea. We call on North Korea to return to diplomacy and cooperation," a Foreign Ministry spokesman said.

The statement was issued by the US State Department after the North Korean state news agency (KCNA) yesterday reported that the country "will completely cut off" all communication lines between the two regions from noon 9/6, copper

North Korea last week threatened to close its liaison office and warned of further steps that would "hurt" South Korea if Seoul did not prevent the defector from sending leaflets and other documents into North Korea.

An unnamed official at the South Korean President's Office acknowledged that the leaflets were often "harmful and unprofitable".