By Kim Young-jin

Seoul is paying close attention over the allegedly tense relations between North Korea and China amid hints of stress following Pyongyang’s failed satellite launch.

A Seoul official expressed concern over a possible third nuclear test by North Korea, Sunday, saying it was a “political option” for Pyongyang following a rocket failure.

“North Korea has its destiny at its discretion (after the nuclear test),” a Cheong Wa Dae official said asking for anonymity.

His comment drew attention as it was taken to mean the North could possibly conduct the nuclear test but the North Korean leadership might be pressed to be mindful of the post-test situation.

The official’s statement came after a warning by President Lee Myung-bak that the North’s continued recalcitrance could fundamentally change the security situation in Northeast Asia, pushing Seoul and Beijing closer while Pyongyang becomes more isolated.

Lee warned that the North’s continued provocations had caused Seoul and Beijing to work closer together, threatening Pyongyang’s key alliance.

He likened the situation to the North’s decades-long strategy of seeking better ties with Washington in a bid to exclude Seoul.

“The North isn’t happy about being pushed aside as South Korea and China move forward together,” he said during a special lecture at Seoul's Education Center for Unification. “Judging by the North’s distress, this appears to be the right approach.”

In a departure from Beijing’s typical calls for regional calm, an editorial in China’s official Huangiu Shibao newspaper warned the North to respect Beijing’s stance on denuclearization, shortly after launch.

Experts saw the editorial as a stern criticism coming just four days after the provocative act.

Beijing, the North’s main ally, supported a U.N. Security Council (UNSC) statement deploring the launch, after protecting Pyongyang from international censure following its military provocations in 2010.

Pyongyang claimed the launch was meant to put a satellite into orbit in celebration of the 100th birth anniversary of its founder Kim Il-sung, but the rocket broke apart shortly after liftoff.

A flurry of reports hinted at Beijing’s displeasure with the move.

The Japanese newspaper Yomiuri Shimbun said China had suspended its repatriation of North Korean defectors in response to Pyongyang’s failure to alert Beijing before launching the rocket.

Another Japanese report said former Chinese foreign minister Li Zhaoxin had been denied entrance to the North celebrations for its late founder amid tension over the launch, which came two days before.

Concerns are rising over the North, which analysts say is working to develop long-range nuclear capabilities in a bid to bolster its military might and deterrence capabilities under its untested leader Kim Jong-un.

Analysts say China prioritizes stability on its borders and therefore works to keep the North Korean regime afloat. It is also speculated Beijing values the North as a buffer zone separating it from U.S troop presence in the South.

In 2010, China prevented any direct blame of Pyongyang in a presidential statement released by the UNSC after the sinking of the South Korean warship Cheonan and opposed a statement against Pyongyang’s deadly shelling of Yeonpyeong Island.

Meanwhile, China and North Korea held high-level talks to discuss issues of regional concern, Saturday.

China’s official Xinhua News Agency reported that Wang Jiarui, the head of the ruling Chinese Communist Party's International Department, met Kim Yong-il, the Korean Workers' Party director of international affairs, for "strategic" talks.

The sides “exchanged views on developing exchanges and cooperation” and “on developments on the Korean peninsula, and on other international and regional issues of common concern," Xinhua reported.