Seoul, South Korea (CNN) -- Tensions between the Koreas remained high Friday as China appeared to criticize the U.S.-South Korean military exercise set to begin Sunday in the Yellow Sea off the west coast of the Korean Peninsula.

"We oppose any party to take any military acts in our exclusive economic zone without permission," Foreign Ministry spokesman Hong Lei said in a statement, according to the state-run Xinhua News Agency.

He said that international law of the sea says that an exclusive economic zone stretches 200 nautical miles from the coast.

The United States is sending the aircraft carrier USS George Washington to join South Korea's forces near the coasts of China and North Korea in the four-day drill. It is set to begin five days after North Korea shelled a South Korean island, killing four South Koreans and wounding 15 others.

North Korea said the South provoked the attack because shells from a South Korean military drill landed in the North's waters. South Korea was holding its annual Hoguk military drill when the North started its shelling.

Xinhua quoted Chinese scholars who also criticized the planned drill by U.S. and South Korean (Republic of Korea) forces. "The United States and ROK should not take sensitive and provocative military actions at such a sensitive time and place," said Major General Luo Yuan, a researcher with the Chinese People's Liberation Army's Military Science Academy.

He likened the planned exercise to "pouring oil onto flames."

But China, North Korea's largest trading partner, also called for an easing of tensions. "As the Korean Peninsula situation is highly complicated and sensitive, all parties concerned should stay calm and exercise restraint," Hong said.

The United States has looked to China to exert its influence on North Korea to ratchet back tensions in the region.

But there was no indication that plan was working. North Korea continued its war rhetoric, saying Friday that South Korea and the United States are recklessly pushing the Korean peninsula toward war by scheduling the joint military drill to begin this weekend.

"The situation on the Korean peninsula is inching closer to the brink of war due to the reckless plan of those trigger-happy elements to stage again the war exercises targeted against [North Korea] in wake of the grave military provocation they perpetrated against the territorial waters of [the North Korean] side in the West Sea," said the North's official KCNA news agency.

The West Sea, part of the Yellow Sea that is nearest to the Koreas, was the scene of Tuesday's shelling.

"The army and people of [North Korea] are now greatly enraged at the provocation of the puppet group, while getting fully ready to give a shower of dreadful fire and blow up the bulwark of the enemies if they dare to encroach again upon [North Korea's] dignity and sovereignty even in the least," KCNA said Friday.

"The group should not run amok, clearly understanding the will and mettle of the highly alerted army and people of [North Korea] to wipe out the enemies."

Chinese Foreign Minister Yang Jiechi met Friday with North Korean Ambassador to China Chi Jae Ryong and talked with U.S. Secretary of State Hillary Clinton and South Korean Foreign Minister Kim Sung-hwan, Xinhua said. "They exchanged views on issues including the situation of the Korean Peninsula," according to a statement released Friday night by the Chinese Foreign Ministry, it added.

The United States has condemned the attack on Yeonpyeong Island and affirmed its military commitments to South Korea.

Also Friday, South Korea named a new defense minister to replace the official who resigned Thursday amid criticism due to North Korea's sinking of a warship in March and Tuesday's deadly shelling of South Korea's Yeonpyeong Island.

South Korea's government nominated Kim Kwan-jin as defense minister, a Blue House media official told CNN.

The National Assembly is to hold a confirmation hearing on the 61-year-old Kim, who served as chairman of the Joint Chiefs of Staff from 2006 to 2008, prior to his retirement.

South Korean and U.S. forces plan to drill in the Yellow Sea from Sunday until Wednesday. The United States has described the drill as defensive in nature. The exercises were planned months ago, and are meant to underscore strong ties between South Korea and the United States, defense officials from both countries have said.

All but about 30 of the island's 1,300 residents have evacuated, with most of them moving to the South Korean mainland, South Korea's Yonhap news agency said. About 100 soldiers and workers also were on the island, doing cleanup and repairs.

The North appeared to have carefully targeted Tuesday's attack, a key South Korean lawmaker said Friday after a visit to Yeonpyeong Island.

"My hunch is that North Korea was picking and choosing its aiming point, they are very focused," said South Korean Congresswoman Song Young-sun, an influential member of the National Assembly's Defense Committee. "They attacked gas station, helicopter pad and command and control sites and water tanks. Everything that is directly related to military operations, they have completely smashed."

Asked why North Korea might have attacked, she said: "I think they are doing this training for dual purposes. One is for South Korea: They are arbitrarily suggesting the different maritime border line from our Northern Limit Line. They are trying to verify what they demand, so they are doing exercises and training."

The expected forthcoming succession of power from North Korean leader Kim Jong-Il to his youngest son, Kim Jong Un, also plays into it, Song said.

"What Kim Jong Un wants to demonstrate is his influence and his exertion of power, because he needs in a very speedy time to prove within the next couple of years that he is strong and qualified to succeed," she said.

The South has scrambled as a result of Tuesday's shelling.

The Cheonan sinking sparked a public uproar, with many saying that it should not have been possible for North Korea to have damaged South Korea's more modern military. North Korea has denied involvement in the sinking.

South Korean President Lee Myung-bak drew criticism for his initial statements after the Yeonpyeong bombardment, when he asked for a stern response but also called for de-escalatory measures to be taken. Later that day, Lee spoke to the military and urged heavy retaliation.

South Korea said Thursday it will strengthen its rules of engagement in the Yellow Sea. South Korean marine forces based in five islands near North Korea and the disputed Northern Limit Line also will be reinforced, a government spokesman said.

The tense maritime border between the two Koreas has become the major military flash point on the Korean peninsula in recent years.

The Yeonpyeong attack was the first direct artillery assault on South Korea since 1953, when an armistice ended fighting, though both Koreas are still technically at war.

Andrew Salmon contributed to this report for CNN.