The South’s military said the exercises were scheduled to take place in the vicinity of the tense Northern Limit Line (NLL), but not near Yeonpyeong island which was hit by a barrage of North Korean shells 13 days ago.
Pyongyang said the drills, expected to last around a week, showed the South was “hell-bent” on setting off a war.
Later in the day in Washington, US Secretary of State Hillary Clinton hosts talks with her Japanese and South Korean counterparts to discuss the North Korean attack.
Among the four South Koreans killed in the attack were two civilians, whose funerals were held on Monday.
“Our country should strengthen our power,” said Kang Seong-ae, whose husband was killed. “I ask earnestly our government to try to be stronger, not to see this kind of tragedy again.”
The prickly North justified the attack — the first of its kind on a civilian area on South Korean soil since the end of the 1950-53 Korean war — saying the South had fired artillery rounds into its waters.
The South said it had been conducting regular drills in the area but that they were harmless and on its side of the NLL.
South Korea’s military said the latest round of naval drills would take place at 29 locations to the west, east and south of the peninsula.
The locations included Daecheong Island, one of five major islands near the NLL off the North’s west coast, and the site of a deadly naval skirmish last year.
The North’s KCNA state news agency said on Sunday the South’s “frantic provocations ... are rapidly driving the situation on the Korean Peninsula to an uncontrollable extreme phase. No one can predict to what extent the situation will deteriorate in the future.”
Tensions have risen to their highest level in decades on the peninsula after the Yeonpyeong attack, which came days after the North’s revelation it had made significant advances in its nuclear program.
The foreign ministers of South Korea and Japan will meet Clinton to discuss North Korea. They are expected to produce a statement condemning Pyongyang’s actions.
China, the North’s only major ally and the chair of stalled international nuclear talks with Pyongyang, is not invited. However, the Washington troika are expected to discuss Beijing’s proposal for emergency regional talks on the crisis.
“These talks aim to discuss ways on how to lead North Korea to act in a good way and the results of the talks will send this message to other countries including Russia and China,” foreign ministry spokesman Kim Young-sun told a news briefing in Seoul.
North Korea disputes the NLL, a sea border established by the United Nations, without Pyongyang’s consent, at the end of the 1950-53 Korean War.
South Korea has sharply increased its rhetoric over the past week, prompted by public opinion polls critical of the conservative government’s perceived weak response to the attack which destroyed dozens of homes.
The South’s new Defense Minister Kim Kwan-jin has vowed to hit back hard against the North if provoked again, saying Seoul will respond with bombs and air power next time.
But in a sign locals from Yeonpyeong do not expect the situation to escalate, an increasing number of residents have returned to their homes in recent days.
South Korean Prime Minister Kim Hwang-shki said on Monday the government would spend $30 billion won ($26.5 million) on rebuilding the island. He added that foreign investment and tourism had been unaffected by the attack.
Analysts say Pyongyang’s latest provocations could be driven by a number of factors including internal politics and its time-honored practice of using threats and violence for leverage to win aid at talks.
Two years ago, North Korea walked out of aid-for disarmament talks — which had brought together the two Koreas, host China, the United States, Japan and Russia.
Pyongyang said its wanted to restart the talks, and has won the backing of Beijing and Moscow, but Washington, Seoul and Tokyo have said they will only return to the negotiating table when the North shows it is sincere about denuclearizing.
