South Korea has pledged to massively step up defenses on an island that came under deadly attack from Communist North Korea as tensions between the two neighbors threaten to reach breaking point.
The pledge from President Lee Myung-bak came as the North raised the prospect of further assaults in response to what it described as "reckless military provocation."
Pyongyang's military bombardment of a tiny South Korean island on November 23 killed four people -- two soldiers and two civilians -- and left 18 injured and others evacuated.
Addressing an emergency cabinet meeting called in response to the attack, Lee said the South had to be prepared for another attack.
"We should not let our guard down in preparation for another possible North Korean provocation," he said. "I think a similar North Korean provocation could come at any time."
Lee's comments came as his office -- galvanized by media criticism of a weak response to the attack -- issued a statement saying that "the existing rules of engagement, which are seen as being rather passive, will be completely revised" to mark a "paradigm shift in responding to North Korea's provocations."
The statement said the military would reinforce ground rules, especially on border islands and define different levels of counterattack "depending on whether attacks are targeted against civilians or the military."
The shelling of Yeonpyeong Island, home to military bases as well a fishing community of 1,300 residents, has triggered the worst crisis for decades in the Korean peninsula and prompted the United States to pressure China to rein in North Korea, its neighbor and putative ally.
North Korea said it launched the attack in response to a South Korean military drill being carried out on the island.
The Chinese foreign minister, Yang Jiechi, has postponed a scheduled visit to the South Korean capital, Seoul.
In Beijing, a Chinese Foreign Ministry, spokesman, Hong Lei, said Jiechi had put the trip on hold "because of his schedule" and added that South Korea had been asked to arrange another date.
He also appeared to sympathize with Pyongyang's complaints about South Korean military maneuvers.
"We hope that relevant parties will put more effort into bringing peace and stability in the region," Hong said. "We are willing to work together with the relevant parties in the effort. As for your second question [on the U.S.-South Korea military drill], we noted the relevant reports and express our concern about this."
He said China and the U.S. had been in close consultations over the crisis.
"China and the U.S. have been talking closely to each other about the situation in the Korean peninsula," Hong said.
On Yeonpyeong, where many homes were reduced to blackened ruins by the attack, the authorities were trying to evacuate the few remaining residents after most islanders had fled following the bombardment.
One local resident, Byun Jae-Soon, summed up the feelings of many as she surveyed a scene of wreckage and rubble on the previously peaceful island.
"It's really indescribable. I cannot say anything," Byun told Reuters. "That kind of fire I couldn't see in the past."
compiled from Reuters and agency reports