North Korea has threatened to disregard the armistice that ended its 1950 to 1953 war with South Korea, if Seoul goes ahead with plans to conduct war exercises with the United States.
The threat made by Pyongyang's supreme military command was published Tuesday in the official Korean Central News Agency.
A separate report in China's official Xinhua news agency said Pyongyang has also decided to halt the work of its delegates at Panmunjom, an abandoned village along the de facto border where Seoul and Pyongyang meet for negotiations.
The threats come as the United Nations Security Council meets Tuesday to discuss new sanctions in response to North Korea's latest nuclear test.
Diplomats say the United States and China have reached a tentative deal to punish Pyongyang for last month's test, its third and most powerful yet.
Diplomats told reporters late Monday they hope the council will be able to vote on a resolution by the end of the week. Details of the draft resolution were not immediately available.
The Security Council already unanimously condemned the February 12 nuclear test as a "grave violation" of existing U.N. sanctions on North Korea's nuclear and missile programs. Pyongyang said its test was aimed at its "arch-enemy," the United States.
China, North Korea's long-time ally, joined the rest of the 15-member Security Council in immediately condemning the test. But diplomats say China has been reluctant to agree to tough action against Pyongyang.
A spokesperson for China's foreign ministry said Tuesday that Beijing would support a "proper and moderate" response from the Security Council, insisting that any action be "conducive to denuclearization, non-proliferation and peace and stability on the peninsula."
Diplomats from Washington and Beijing have for weeks been in talks aimed at expanding or adding a fourth round of sanctions against the impoverished Communist state. Speaking anonymously, several diplomats have said both sides are nearing a deal.
North Korea is already under tough sanctions as a result of its previous nuclear tests in 2006 and 2009. In January, the Security Council expanded those sanctions in response to a December rocket launch.
The North says its latest tests prove that it can strike the mainland U.S. with a long-range missile. It has angrily rejected the U.N sanctions, and threatened to carry out more missile and nuclear tests in response to what it says is U.S. hostility.
South Korea and North Korea have been in a technical state of war for more than 60 years. The agreement that ended the 1950 to 1953 civil war hostilities was only a truce.
About 28,500 American troops are stationed across the border in South Korea, and the two sides regularly conduct military drills. The latest were to begin on March 1st with a month-long series of air, ground and naval exercises known as Foal Eagle. Separately, a two-week, computer-based simulation called Key Resolve, is set to begin on March 11th.
The allies' say the exercises are designed to enhance the security and readiness of South Korea and insists they are deterrent in nature. The North sees the drills as preparation to invade its territory.