South Korea will withdraw all its nationals from a troubled jointly-run resort in North Korea after Pyongyang warned them to leave and seized Seoul-owned properties there, an official said on Tuesday. All 14 South Korean workers at the Mount Kumgang tourist resort will return across the heavily-fortified land border on Tuesday, said a spokeswoman of Seoul's Unification Ministry, which handles cross-border affairs. The group are employees of Seoul-based Hyundai Asan and other firms that have helped maintain the resort, she said, adding that two Chinese workers would join them. The move comes a day after the North seized all Seoul-owned properties in the resort, worth millions of dollars, and ordered all South Koreans to leave within 72 hours amid high cross-border tension. The scenic resort, developed by the South's Hyundai Asan and opened in 1998, was a vital source of hard currency for Pyongyang, once earning the North tens of millions of dollars a year. But the South suspended tours by its citizens after a North Korean soldier shot dead a South Korean tourist who had strayed into a restricted zone in July 2008. It has said it will not restart them until the North allows an on-site investigation into the shooting and gives firm safety guarantees. Past talks to resume the symbolic tour have produced little as cross-border ties turned icy after Seoul accused Pyongyang of torpedoing its warship with the loss of 46 lives in March 2010. The North angrily denied the charge but went on to shell a border island that left four South Koreans dead and sparked brief fears of a possible war in November last year, prompting Seoul to cut most trades and aid.