North Korean leader Kim Jong-un has ordered his troops to bury enemies at sea if provoked, Pyongyang's state media reported, amid tensions over his country's planned rocket launch.

Kim also called on the troops to further strengthen the defense of an islet on the east coast as "an iron wall" to ensure no enemies can invade his country under any circumstances.

North Korea frequently claims that the United States has a hostile policy toward Pyongyang and regularly holds military exercises with South Korea as rehearsals for a northward invasion.

South Korea and the U.S. say the routine joint military maneuvers are aimed at bolstering their readiness against a possible North Korean provocation.

Kim ordered the unit on Ryo Islet "to send all the intruders into the bottom of the sea," during his inspection tour, the North's official Korean Central News Agency reported in an English-language dispatch late Wednesday.

North Korea has a track record of deadly provocations against South Korea.

In March 2010, 46 South Korean sailors were killed in the sinking of their warship near the two Koreas' disputed western sea border.
A team of multinational investigators concluded in 2010 that a North Korean torpedo was responsible for the sinking. However, the North still adamantly denies its involvement.

Kim has made frequent trips to military units in an apparent attempt to bolster his support from the military since he took over the country upon his father's death in December.

Kim's latest inspection comes amid international pressure on the North to call off its planned long-range rocket launch.

The North says the launch set for sometime between April 12 and 16 is designed to put an earth observation satellite into orbit.

However, South Korea, the U.S. and other regional powers suspect the launch could be a cover for testing the North's ballistic missile technology, which is banned under a U.N. resolution.

A satellite photo shows more vehicles, including trailers, on the launch pad and fuel and oxidizer containers at the fuel system next to it, according to IHS Jane's Defense Weekly image analyst Allison Puccioni.

She said the gantry crane above the launch tower is now situated directly over the mobile launch platform, the position necessary to erect the rocket, citing the March 31 image taken by GeoEye.

"The level of activity at the launch pad and tower indicates that the rocket should be in place within days," she said in a comment sent to Yonhap News Agency. (Yonhap)