Nuke test gives US 'excuse to boost its military'(2)

Even if the DPRK conducts its fourth and fifth nuclear tests, that will never increase its negotiating power, she said. Only when Pyongyang tries to abandon its nuclear weapons can its negotiating power rise, she added.

The ROK military said on Wednesday Seoul has deployed missile systems covering the whole territory of the DPRK, to cope with Pyongyang's nuclear threats, according to the Yonhap news agency.

The agency cited a Seoul foreign ministry official as saying that Seoul's countermeasures focus on how to limit the money, technology and spare parts which Pyongyang's nuclear test requires, but will not include military means.

Ruan Zongze, vice-president of the China Institute of International Studies, said Seoul needs to soothe domestic worries over the DPRK's nuclear test.

Wang, from the China Foreign Affairs University, said Seoul's military countermeasures will help Washington and its allies strengthen their military power in the region.

Leaders of the US, Japan and the ROK discussed the nuclear issue over the phone.

US President Barack Obama guaranteed ROK President Lee Myung-bak that the US will offer protection to the ROK to cope with possible DPRK threats, according to Yonhap.

This shows that the US may use Pyongyang's test as an excuse to push for military deployment in East Asia, a scenario that will only increase regional tension, Ruan said.

The UN Security Council had an emergency meeting on Tuesday in New York.

"The members of the Security Council will begin work immediately on appropriate measures in a Security Council resolution," the council said in a statement.

Bruce Klingner, a senior research fellow for Northeast Asia at the Heritage Foundation in Washington, said the DPRK had again defied the UN and recent efforts by China to prevent its neighbor from ratcheting up tension.

'No health impact'

Pyongyang's nuclear test has not had a negative impact on China's environment or public health, the Ministry of Environmental Protection said on Wednesday.

Readings from 25 monitoring stations, on and near the border, were at normal levels by 10 am, it said. The test site is about 100 km away from the border.

Chen Weihua in Washington contributed to this story.