SEOUL, South Korea - North Korea's powerful National Defense Commission accused South Korea on Friday of faking the sinking of a warship for which Pyongyang has been blamed and warned that the Korean peninsula was heading to "the brink of war."

The comments were similar to other recent pronouncements but were made at a news conference, which is an extremely rare occurrence for the commission, the most powerful organ in the North and which is chaired by leader Kim Jong Il.

It came as international pressure mounted on Pyongyang, and South Korea said the premier of the North's closest ally China said his country would "defend no one" once it decides who was responsible for the sinking.

A multinational investigation concluded last week that a North Korean submarine fired a torpedo that tore apart and sank the Cheonan in late March, killing 46 sailors in the worst attack on the South Korean military since the Korean War. North Korea has denied responsibility and warned that retaliation or punishment would mean war.

"The South Korean puppet regime's faked sinking of the Cheonan has created a very serious situation on the Korean peninsula, pushing it towards the brink of war," Maj. Gen. Pak Rim Su, director of the department of policy at the National Defense Commission, told a news conference in Pyongyang, according to broadcaster APTN.

Tensions have soared since South Korea laid out a series of punitive measures and pledged to haul Pyongyang before the U.N. Security Council. The steps include slashing trade, resuming anti-North Korean propaganda broadcasts across the border and launching large-scale naval exercises off the western coast. U.S.-South Korean military drills are to follow in the coming months.

"These anti-North Korean confrontations are an open declaration of war against us and an extraordinarily criminal act that pushes inter-Korean relations into a state of war," Pak said.

He also said that Seoul's resumption of psychological operations near the border was "sharpening possibilities for one-on-one confrontation at an unprecedented speed."

A number of people attended the news conference, including some foreigners who may have been Pyongyang-based diplomats. A uniformed foreign military officer could be seen watching the proceedings, which were aired in full on state television.

In Seoul, Chinese Premier Wen Jiabao told South Korean President Lee Myung-bak that his country "will defend no one" once it determines who was responsible for the sinking, the South Korean government said.

While South Korea, the U.S. and Japan have condemned North Korea, China has taken a cautious position.

China's backing would be key to any bid to condemn or sanction North Korea. Beijing, a veto-wielding permanent UN Security Council member, so far has refrained from committing to council action against Pyongyang, its neighbor and traditional ally.

China will decide its stance after considering international probes and the reactions of all countries, Wen told Lee, according to a briefing by presidential adviser Lee Dong-kwan.

Wen's comments could not be independently confirmed. China's official Xinhua News Agency made no mention of a pledge not to defend those responsible in its report on the meeting. However, Xinhua did quote Wen as saying China would make a judgment on the cause of the incident in an "objective and fair manner" and "take its stance on the basis of facts concerning the sinking of a South Korean warship."

China "always opposes and condemns any acts detrimental to peace and stability on the peninsula," it quoted him as saying, adding that Beijing "takes serious note of the results of a joint investigation by South Korea and other countries, as well as the reactions of all parties."

Wen's remarks appear to show China is sensitive to South Korean anger over the sinking and rising criticism of Beijing's reluctance to endorse the investigation results or criticize Pyongyang.

Chinese leaders were pressed hard on the issue during talks with U.S. Secretary of State Hillary Rodham Clinton and other officials in Beijing earlier this week, and Seoul has already expressed its displeasure over Beijing's hosting the North's reclusive leader Kim Jong Il on a visit just weeks after the sinking.

Wen's pledge not to defend the perpetrators, as reported by South Korea, may also be a sign that Beijing won't exercise its veto at the Security Council. That would likely be conditional on any measures taken against the North being symbolic and unlikely to further destabilize the regime.

Wen and Lee met at the Blue House a day before a three-way summit that will also include Japanese Prime Minister Yukio Hatoyama.

Lee met Wen for 100 minutes, 60 longer than planned, according to Lee, the presidential adviser. The president explained the results of the investigation and gave Wen a Chinese language summary.

North Korea has carried out a series of attacks on the South since the Korean War ended in a truce in 1953. South Korea has never retaliated militarily. China fought with North Korea in the war, while the U.S. aided the South.