SEOUL— South Korea says China has agreed to cooperate in opposing North Korea's threat to test a fourth nuclear device. The agreement was reached during a meeting with China's visiting top diplomat in anticipation of a state visit by President Xi Jinping. But political analysts disagree on whether it is in Beijing's best interest to further pressure Pyongyang to give up its nuclear programs.
South Korean Foreign Minister Yun Byung-se says he and his Chinese counterpart, Wang Yi, agree Pyongyang's nuclear activities are a serious threat to peace and stability in the region.
Pyongyang is threatening to test a fourth nuclear device in defiance of United Nations resolutions. The bluster follows U.N. and international condemnation in March of a series of rocket launches that experts say are veiled tests for ballistic missiles.
China has been reluctant to publicly and explicitly warn its neighbor and historic ally against the tests.
But after Ministers Yun and Wang met Monday in Seoul, South Korea's Foreign Ministry issued a statement saying they agreed on the nuclear issue.
It said the two sides would strengthen cooperation against North Korea's nuclear tests and urge meaningful dialogue for Pyongyang to give up its nuclear programs. The statement said they agreed not to accept North Korea as a nuclear power.
Jung Jae-heung, a researcher at the Institute for Far Eastern Studies of Kyungnam University, says it is in China's best interest to be more strict with North Korea.
He says if North Korea conducts a fourth nuclear test, then security in the region will become unstable. That would make South Korea, the United States and Japan strengthen cooperation, which would affect the security concerns of China.
But China's official statements on the ministers' meeting made no mention of opposing North Korea's threatened nuclear test.
The official Xinhua news agency said Wang urged all sides to refrain from activity that threatened peace in the region and repeated calls for six-nation negotiations.
North Korea's top nuclear negotiator met with former U.S. officials in Mongolia last week to discuss the issue. Although unofficial, the talks were seen as a positive step to possibly reviving negotiations.
Minister Wang also met with South Korea's President Park Geun-hye who called for North Korea to at least suspend its Yongbyon nuclear plant and threats of a test.
The China-hosted denuclearization talks with the two Koreas, Japan, Russia, and the United States were last held in 2008. Since then, North Korea tested a second and third nuclear explosive and numerous rockets before declaring its intention to talk.
Beijing support an unconditional return to talks but Seoul, Tokyo, and Washington want to see sincere gestures from Pyongyang.
Heo Jai-chul, a research professor at the Korean-Chinese Relations Institute of Wonkwang University, says there is no doubt Beijing opposes Pyongyang's nuclear tests, but that does not mean it sees the same solution as Seoul.
He says China sees North Korea’s nuclear development as a security threat but one that originates from the (military) alliance between South Korea and the United States. So he expects China will suggest South Korea and the U.S. refrain from military exercises to help prevent North Korea’s nuclear testing.
China lost hundreds of thousands of soldiers fighting on North Korea's side against U.S.-led U.N. forces in the 1950s Korean War. The three-year conflict ended with an armistice rather than a peace treaty that keeps Korea, technically, in a state of war with occasional hostilities.
In contrast, relations between South Korea and China quickly warmed over economics and a mutual historic grievance over Japan. China is South Korea's top trade partner while South Korea ranks China's fourth largest.
Beijing supported past U.N. resolutions against North Korea for its nuclear and missile programs and restricted some trade and financial dealings.
But researcher Jung says it is not clear if a fourth nuclear test would prompt Beijing to back tougher sanctions.
He says if China used strong economic sanctions against North Korea it could collapse and trigger a wave of North Korean refugees into China. He says North Korean nuclear weapons could be leaked to groups related to terrorism, posing a threat to China’s security. So, it would be more difficult for China to impose sanctions against North Korea than what we think.
Despite the differences on dealing with North Korea, China called relations with South Korea the best they have ever been.
Ministers Yun and Wang discussed an expected visit to South Korea by China's President Xi Jinping that could come as early as June.
South Korea's Joongang Daily newspaper reports it would be the first visit by a Chinese president to Seoul before visiting Pyongyang in nearly two decades.
That would send a signal to North Korea that while China is increasingly uneasy with its old ally it is becoming closer to its historic enemy.
VOA Seoul bureau producer Youmi Kim contributed to this report.