North Korea said yesterday it will expel "unnecessary" South Koreans from a mountain resort in the North from today after tensions escalated last month when one of its soldiers shot dead a South Korean tourist at the enclave.

Housewife Park Wang-ja, 53, was gunned down when she wandered into a sparsely demarcated military area at the scenic Mount Kumgang resort, just north of the heavily militarised border and run by an affiliate of the South's Hyundai Group.

"The measure of expelling personnel of the South side unnecessary in the tourist area of Mount Kumgang shall take effect from August 10," the North's official KCNA news agency cited a military official as saying. Seoul has been angered by the North's refusal to co-operate in an investigation into the shooting while Pyongyang has demanded an apology. South Korea showed its displeasure at the North's most recent move with a Unification Ministry spokesman saying at a news briefing:

"North Korea has no grounds for forcing them out, unless their stay is against the law."

Ties between the Koreas have soured since South Korean President Lee Myung-bak took office in February and said that the free flow of aid the North had seen under his predecessors would be cut and Seoul would tie its largesse to how Pyongyang behaves.

Nearly two million South Koreans have visited the Kumgang resort since it opened in 1998 and was hailed as a milestone in reconciliation between the two countries, technically still at war, who station more than one million troops near their border.