North Korea's young leader Kim Jong-un has given a secret order to thoroughly check the Punggye-ri nuclear test facility to pave the way for a third nuclear test, South Korean media reported Wednesday.

Officials and experts previously speculated that North Korea may choose February 16, the birthday of the country's late leader Kim Jong-il, or February 25, the day of the inauguration ceremony of South Korea's president-elect Park Geun-hye, to conduct a fresh nuclear test, the Joongang Daily said.

But the date has been brought forward by Kim in response to the UN Security Council resolution that "deplored" North Korea's rocket launch last December and expanded the list of existing sanctions against Pyongyang.

Kim made the decision in a Saturday meeting with a new panel of top security officials and diplomats, the newspaper said.

According to the report, Kim has ordered all North Korean troops to enter a state of emergency from midnight Tuesday, and ordered the troops along the border between the two Koreas and in the neighborhood of Pyongyang to prepare for war, in a clear indication that an early nuclear test was underway.

The North's National Defense Commission has threatened a "higher-level" nuclear test and its foreign ministry vowed to boost the country's military capability, including nuclear deterrence, immediately following the UN resolution.

The Yonhap News Agency on Wednesday, citing military and intelligence sources, also reported recent signs of increased activity of workers and vehicles at the Punggye-ri nuclear test facility in the northeast of North Korea.

Analysts said that if North Korea pushes for an early nuclear test, the timing would "not be so good."

"Kim Jong-un faces the heavy task of fixing the North's crippled economy. If he is really determined to defy pressure from the international community and let a third nuclear test go ahead, I would say he is too immature, compared with his late father, when it comes to handling regional relations," said Lü Chao, a researcher on Korean Peninsula issues at the Liaoning Academy of Social Sciences.

"North Korea will risk a full-fledged sanction targeting its defense capabilities following a nuclear test that the international community, including China, has seriously warned against," Lü added.

China's foreign ministry spokesperson Hong Lei on Wednesday again called for all concerned parties not to take actions to further escalate tension or to sabotage the efforts to realize the denuclearization of the Korean Peninsula.

Japan and South Korea on Wednesday also pledged joint efforts to dissuade Pyongyang from carrying out a third nuclear test.

US Secretary of State Hillary Clinton said Tuesday that the North's menacing rhetoric has disappointed US expectations that Kim Jong-un would be different from his father, but Washington still hopes to persuade Pyongyang to change course.

But the North's official Korean Central News Agency said in a commentary piece on Wednesday that the US is "chiefly to blame for the nuclear issue on the peninsula and has driven the situation into an extreme phase where it is hard to settle the issue."

Cui Zhiying, director of the Korean Peninsula Studies Center at Tongji University, said he believes that North Korea was intentionally trying to destroy the atmosphere for talks.

"Pyongyang is intentionally creating tensions before the incoming South Korean President Park has a chance to engage with the North or US President Barack Obama has a chance to shape his North Korea policy for his second tenure. North Korea believes that by making these moves it can increase its stake in future negotiations with any parties," Cui told the Global Times.

Rumors on the Internet said that on this occasion, North Korea might change the site for the planned nuclear test and it could take place as close as 20 kilometers away from the Chinese border with North Korea.

These rumors have touched the nerves of some Chinese people, who expressed their concerns over the potential hazards on the Internet.

However, residents living near the border with the North showed little concern, though the nuclear test in 2009 triggered tremors that could be felt on the Chinese side of the border.

"I learned the information (about North Korea's ongoing preparation for nuclear test) from the Internet, but I am not worried about it at all," said a lawyer who lives in Yanji, Jilin Province, only 50 kilometers from the China-North Korea border.

Agencies contributed to this story

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