The South Korean military notched up its defense posture on Wednesday and vowed stern punishment against North Korea’s provocations after Pyongyang warned of retaliation for imminent U.N. Security Council sanctions and Seoul-Washington joint military drills.

North Korea’s military leadership late Tuesday threatened to launch “nuclear strikes,” annul the inter-Korean truce, close its office in the border village of Panmunjom, and cut off its military hotline with the United Nations Command.

“The drills are, as the North was informed, annual South Korea-U.S. joint exercises for the defense of the Korean Peninsula,” said Maj. Gen. Kim Yong-hyun, the Joint Chiefs of Staff’s head of operations, at a news conference at the Defense Ministry in Seoul.

“If North Korea nonetheless pushes ahead with provocations that would threaten the lives and safety of our citizens, our military will strongly and sternly punish the provocations’ starting point, its supporting forces and command. We are making it clear that all preparations are completed.”

The heightened threat was carried in a statement by the Supreme Command of the (North) Korean People’s Army and announced by Kim Yong-chol, the hard-line chief of North Korea’s Reconnaissance General Bureau. He was lately reinstated to a four-star general three months after being demoted to two-star rank.

The RGB is believed to have masterminded a series of attacks against the South including the sinking of the corvette Cheonan and the shelling of Yeonpyeong Island, both in 2010, and a 2011 cyber attack that paralyzed the National Agricultural Cooperative Federation’s banking system for several weeks.

In New York, the U.N. Security Council will approve its fourth batch of sanctions as early as Thursday in punishment of Pyongyang for its nuclear test on Feb. 12. The newest measures are expected to include asset freezes, tighter cargo inspection, travel bans for core individuals and restrictions on the transfer of bulk cash.

Seoul and Washington started their Foal Eagle field training program on March 1 for a two-month run and are scheduled to launch 10-day computer-simulated drills named Key Resolve on Monday.

The North is also predicted to stage a nationwide military exercise next week, mobilizing a standing army and backup forces including laborers and farmers. 

Late last month, Pak Rim-su, the North Korean military representative at Panmunjom, sent a telephone message to U.S. Forces Korea Commander Gen. James Thurman and warned against “a war of aggression by staging the reckless joint military exercises.”

“When the war exercises reach their main phase after March 11, the Korean War armistice agreement, which has existed in its name only, will come to an end,” the KPA statement reads.

To better cope with escalating tensions, Cheong Wa Dae said it will hold a chief secretary meeting every morning under Chief of Staff Huh Tae-yeol.

Concerns are rising over President Park Geun-hye’s ability to handle the high-stake issue with the much-touted national security office still not in place amid festering partisan disputes over her overall government reshuffle plans and an ensuing administrative vacuum.

The Tuesday meeting took place without Kim Jang-soo, a former defense minister who was named to steer the organization. He is being separately briefed on the situation and related developments, government sources said.

“We are under abnormal conditions in which Kim is unable to attend the senior secretary meeting because of delays in passing the government reform bill,” presidential spokesperson Yoon Chang-jung told reporters early in the day.

“But the National Security Office is substantively examining and responding to the situation in close cooperation with the administration including the Defense Ministry and military.”

By Shin Hyon-hee (heeshin@heraldcorp.com)