Seoul, South Korea ? North Korea agreed today to allow South Koreans working in a joint industrial zone in North Korea to cross the border after Pyongyang’s move to cut the last military hot line to Seoul left hundreds stranded overnight, officials said.

North Korea put its troops on alert and cut the hot line Monday as the American and South Korean militaries began joint maneuvers. The communist regime warned that even the slightest provocation could trigger war during the 12-day drills.

The North stressed that provocation would include any attempt to interfere with its impending launch of a satellite into orbit. U.S. and Japanese officials fear the launch could be a cover for a test of a long-range attack missile and have suggested they might move to intercept the rocket.

The North has been on a steady retreat from reconciliation since President Lee Myung-bak took office in the South a year ago. After Lee said the North must continue dismantling its nuclear program if it wants aid, Pyongyang cut ties, suspended joint projects and stepped up its belligerence rhetoric.