North Korea's state news agency announced Sunday that the country was poised to launch a powerful retaliatory strike on South Korea, if military exercises conducted by Seoul encroach upon its territorial waters.

The Korean Central News Agency (KCNA) reported that new leader Kim Jong Un issued the order while visiting the 1st and 4th Battalions of the Korean People's Army 4th Corps, based near the border with the South.

The agency said Kim had told troops to stay alert, claiming the area was a "hot spot where a war may break out any moment due to the enemy's reckless provocations for aggression."

"He ordered them to make a powerful retaliatory strike at the enemy, should the enemy intrude even 0.001 millimeter into the waters of the country where its sovereignty is exercised," KCNA said.

The agency added that the 4th Battalion was responsible for the shelling of Yeonpyeong Island in November 2010, an attack that killed four South Koreans and two civilians. At the time, the North said a military drill near the disputed maritime border had provoked the bombardment.

The agency said Kim, who took control of the 1.2-million-strong military following the death of his father Kim Jong-Il in December, "highly appreciated the feats" of battalion members.

The North Korean report came a day before the beginning of Key Resolve, a joint US-South Korean exercise, which continues until March 9. The allies claim the operations are mainly computer-simulated and defensive in nature.

The country's powerful National Defense Commission on Saturday threatened a "sacred war" over the drills.

Tension has been high since Seoul accused Pyongyang of sinking a warship off the west coast in March 2010, killing 46 sailors.

rc/cmk (AP, dpa, Reuters)