Updated

A top Chinese Communist Party (search) official was in North Korea's capital Sunday seeking to draw Pyongyang back into six-nation talks on its nuclear weapons program after the North reportedly rejected further negotiations.

The visit by the Chinese official, Wang Jiarui, came as Secretary of State Condoleezza Rice (search) and Defense Secretary Donald H. Rumsfeld (search) met with their Japanese counterparts and urged North Korea to rejoin the stalled negotiations. Rice called the six-party talks "the best way to end nuclear programs and the only way for North Korea to achieve better relations."

Chinese state media said Wang "exchanged views ... on international and regional issues" with North Korea's No. 2 leader, Kim Yong Nam.

China's effort to persuade North Korea to rejoin negotiations has taken on greater urgency since Pyongyang's unconfirmed declaration earlier this month that it has become a nuclear power. Beijing (search) is a key source of food and energy aid to the impoverished North but fears that cutting off supplies might risk instability and send a flood of refugees across the border into China.

Wang, who arrived in Pyongyang (search) Saturday for a four-day visit, also planned to meet with North Korean leader Kim Jong Il, according to South Korea's Munhwa Ilbo newspaper.

China's state news agency, Xinhua, reported Saturday that the North had reiterated its Feb. 10 decision to indefinitely suspend participation in six-party talks with the United States, South Korea, China, Japan and Russia.

During three rounds of talks in Beijing since late 2002, North Korea has demanded more aid and a peace treaty with Washington in exchange for abandoning nuclear development.

North Korea had also sought one-on-one talks with Washington but withdrew that offer on Saturday, citing what it called the United States' persistent attempts to topple the communist regime, Xinhua reported.

In Washington, Japan's foreign minister, Nobutaka Machimura, said he hoped China "will serve the role not just as a mere moderator, but also as a player actively at work on the North Koreans" to rejoin the talks.

In response, North Korea criticized Japan's new defense guidelines, which singled out North Korean missiles as a threat and allowed Japan to pursue a missile defense program with Washington. According to Pyongyang, the guidelines adopted in December were a sign that Tokyo has joined "U.S. vicious hostile policy" toward its communist state.

U.S. naval vessels, including a nuclear-powered submarine, joined South Korean ships in a weeklong exercise on South Korean waters off the east coast, according to a news report Sunday.

South Korea's navy said Sunday the anti-submarine exercise took place Feb. 12-18 in the East Sea.

U.S. military officials could not immediately confirm the report, but South Korea's Yonhap news agency said a Los Angeles-class nuclear submarine and other U.S. vessels joined the exercise.

North Korea routinely condemns joint military exercises between the United States and South Korea, calling them preparations to invade the communist state.