North Korea's military threatened "strong physical retaliation" against planned South Korean naval drills near their disputed sea border and warned civilian ships should stay away from the area.
South Korea plans to hold five-day naval drills in the Yellow Sea, including exercises near the border, beginning Thursday in response to the deadly March sinking of a South Korean warship blamed on North Korea. Forty-six sailors were killed. Pyongyang vehemently denies downing the 1,200-ton Cheonan, and has asked to send its own investigators to examine the results of the probe into the sinking. Seoul has rejected the requests. North Korea will "counter the reckless naval firing projected by the group of traitors with strong physical retaliation," the military said Tuesday in a statement carried by Pyongyang's official Korean Central News Agency.
The military also warned civilian ships to stay away from the maritime border.
The western maritime boundary has long been a flash point between the two Koreas because the North does not recognize the border unilaterally drawn by the United Nations at the close of the 1950-53 Korean War.
North and South Korea have fought three bloody skirmishes near the maritime border in recent years, most recently in November 2009. South Korean defense officials said they had no comment on North Korea's latest threat.
In Washington, State Department spokesman P.J. Crowley urged North Korea not to take further provocative steps. "We certainly don't want to see a conflict in the region," Crowley said Tuesday. "We would hope that North Korea, for its part, will avoid any further provocative actions."
North Korea routinely issues such threats, especially when the South holds joint military drills with the U.S., as they did last month. Pyongyang sees the exercises as a rehearsal for an invasion. The U.S. has 28,500 troops in South Korea to protect the longtime ally.
The North had threatened to respond to those exercises with "nuclear deterrence" but South Korean military officials said there was no sign of unusual North Korean military activity. Washington and Seoul say their exercises are purely defensive, but the recent naval drills off South Korea's east coast were intended to warn the North that further provocations will not be tolerated.
U.S. forces are not taking part in the drills planned to start Thursday.
Meanwhile, North Korean Foreign Minister Pak Ui Chun called Tuesday for peace on the Korean peninsula and repeated Pyongyang's long-standing demand for a peace treaty to replace the cease-fire signed in 1953.
"We are pressing for a peace treaty to get rid of the root of constant threats against peace and stability in the region and to ensure permanent peace on the Korean peninsula," he said in a speech in Jakarta, Indonesia.
Pak denied North Korea sank the Cheonan and said during talks Monday that Pyongyang was ready to return to nuclear disarmament talks, Indonesian Foreign Minister Marty Natalegawa said. North Korea walked away from nuclear talks hosted by China in 2009.