YEONPYEONG ISLAND, South Korea - Military maneuvers planned by South Korean troops did not take place Saturday because of bad weather on a border island shelled by North Korea last month, as the U.N. Security Council scheduled an emergency meeting at Russia's request amid concerns over rising tensions on the divided peninsula.

The North warned Friday that it would strike even harder than before if the South went ahead with planned one-day firing drills it says it will conduct sometime between Saturday and Tuesday. Four people died last month in the North's attack on Yeonpyeong Island near the tense sea border.

The U.S. supports South Korea, saying the country has a right to conduct such a military exercise. However, Russia's Foreign Ministry expressed its "extreme concern" Friday over the drills and urged South Korea to cancel it to prevent a further escalation of tensions.

The U.N. Security Council scheduled emergency closed-door consultations on North Korea for this morning at Russia's request, said Mark Kornblau, spokesman for the U.S. Mission to the United Nations. The United States holds the council's rotating presidency this month.

China, the North's key ally, said it is firmly against any acts that could worsen already-high tensions on the Korean peninsula. "In regard to what could lead to worsening the situation or any escalation of acts of sabotage of regional peace and stability, China is firmly and unambiguously opposed," Chinese Foreign Ministry spokeswoman Jiang Yu said in a statement Saturday.

China's Vice Foreign Minister Zhang Zhijun also warned in a statement that the situation on the Korean peninsula is "extremely precarious."

The North issued a warning Saturday saying South Korea would face "catastrophe" if it went ahead with the planned drills, the Foreign Ministry said in a statement carried by the official Korean Central News Agency.

South Korea's Joint Chiefs of Staff said Saturday that marines would go ahead with the drills as scheduled and that the military was ready to respond to any possible provocation.

Foreign Ministry spokesman Kim Young-sun said the drills are defensive in nature and are not aimed at stoking regional tensions.

The artillery drills were not expected to be held over the weekend because of bad weather and will be conducted either Monday or Tuesday, a Joint Chiefs of Staff officer said on condition of anonymity, citing department rules.

Marines carrying rifles conducted routine patrols Saturday morning on Yeonpyeong, and no warning for residents to evacuate to underground shelters had been issued. About 300 residents, officials and journalists remain on Yeonpyeong, but officials from Ongjin County, which governs the island, said they had no immediate plans to order a mandatory evacuation to the mainland.

"North Korea said it will deal the powerful ... blow at us if we go ahead and fire artillery. So residents are getting more restless," said Yoon Jin-young, a 48-year-old islander.

Later Saturday, activists launched balloons containing about 200,000 propaganda leaflets toward the North from the island, which is only about seven miles (11 kilometers) from North Korean shores. The balloons also carried 1,000 $1 bills and DVDs containing information on the North's artillery barrage last month.

Several bloody naval skirmishes occurred along the western sea border in recent years, but last month's assault was the first by the North to target a civilian area since the end of the 1950-53 Korean War. The North does not recognize the U.N.-drawn sea border in the area.

The North claims South Korea fired artillery toward its territorial waters before it unleashed shells on the island last month, while the South says it launched shells southward, not toward North Korea, as part of routine exercises.

In Washington, State Department spokesman P.J. Crowley said Friday that North Korea should not view South Korea's upcoming drills as a threat.

"A country has every right to train and exercise its military in its own self-defense," Crowley said. "North Korea should not use any future legitimate training exercises as justification to undertake further provocative actions."

Still, Gen. James Cartwright, vice chairman of the Joint Chiefs of Staff, voiced concerns of a potential chain reaction if the drills are misunderstood or if North Korea reacts negatively. "What you don't want to have happen out of that is for us to lose control of the escalation," he told reporters at the Pentagon.

A flurry of regional diplomacy was under way to defuse the tensions, with New Mexico Gov. Bill Richardson visiting the North.

A frequent unofficial envoy to the reclusive country, Richardson said he wanted to visit the North's main nuclear complex and meet with senior officials during his four-day trip, though details of his schedule were unclear.

"My objective is to see if we can reduce the tension in the Korean peninsula," Richardson said Thursday at the airport in Pyongyang, according to Associated Press Television News.

U.S. Deputy Secretary of State James Steinberg held closed-door meetings Thursday with Chinese State Councilor Dai Bingguo. Beijing's top foreign policy official returned last week from talks in Pyongyang with North Korean leader Kim Jong Il. China has come under growing pressure to push North Korea to change its behavior.

In New York, U.N. Secretary-General Ban Ki-moon called the Nov. 23 attack on Yeonpyeong "one of the gravest provocations since the end of the Korean War."

Ban, a former South Korean foreign minister, urged North Korea to show restraint and called on both Koreas to reduce tensions on the Korean peninsula.