SEOUL, South Korea –  North Korea vowed Tuesday to cancel the 1953 cease-fire that ended the Korean War, citing a U.S.-led push for punishing U.N. sanctions over its recent nuclear test and ongoing U.S.-South Korean joint military drills.

Without elaborating, the Korean People's Army Supreme Command warned of "surgical strikes" meant to unify the divided Korean Peninsula and of an indigenous, "precision nuclear striking tool." The statement came amid reports that Washington and North Korean ally Beijing have approved a draft of a U.N. Security Council resolution calling for sanctions in response to North Korea's Feb. 12 nuclear test. The draft is expected to be circulated at the U.N. this week.

Such heated military rhetoric and threats are common from North Korea as tensions rise on the Korean Peninsula, and Pyongyang's recent nuclear test and rocket launches, and the push for U.N. punishment that have followed, have increased already high animosity between the North and Washington and ally Seoul....