South Korea has decided to sharply bolster its military arsenal in the tense Yellow Sea to counter any possible additional attack from North Korea, the presidential office Cheong Wa Dae said Thursday.

 It also announced a plan to overhaul the military's policy on the use of force against North Korea at the outbreak of a skirmish.

 The decision came after the North bombarded South Korea's front-line Yeonpyeong Island and surrounding waters in the Yellow Sea, a long-time flash point between the rival militaries, on Tuesday. The shelling killed two South Korean marines and as many civilians and wounded more than a dozen others.

 "We should not release our sense of crisis in preparation for the possibility of another provocation by North Korea. A provocation like this can recur any time," President Lee Myung-bak was quoted as saying in an emergency meeting with security and economy ministers.

 The president instructed that the troops on the five islands in the Yellow Sea, the most vulnerable region to the North's belligerent behavior, be equipped with the world's top-level weapons, according to his spokeswoman Hong Sang-pyo.

 In a related move, the government will allocate more of its budget to reinforcing combat capability in the Yellow Sea archipelago and scrap the former administration's plan in 2006 to gradually scale down the presence of marine corps there, he said.

 He added the military will make an "across-the-board" change in the rules of engagement against the North's military attacks.

  "As our existing rules of engagement have been assessed as rather passive, focusing on preventing the escalation of a conflict, the government has decided to make new rules of engagement to change the paradigm itself of responding to North Korea's provocation," Hong said.

 For example, a clear line will be drawn between a response to attack the military and one against civilians, he added.

 The South has also decided to fully carry out economic punitive measures against the North that were imposed in May after the North's deadly torpedo attack on a South Korean warship.

  "As to civilian groups' aid to North Korea, the government will review whether to provide support (to the groups) in consideration of various situations including public sentiment and South-North Korean relations," he said.

   Seoul will also continue diplomatic efforts to pressure Pyongyang to change its behavior. "In particular, the government will double efforts to secure China's constructive role," Hong said.

   On the economic front, the government plans to take "preemptive measures" to stabilize the financial market and maintain a "24-hour monitoring system," he said. (Yonhap News)