Nam Sung-Wook, a North Korea expert and professor at Korea University, identified Pak Jae-Gyong, Hyon Chol-Hae and Lee Myong-Su as the key drivers of Kim's brinkmanship.

"The trio, accompanying Kim like shadows, were definitely behind the decision to push ahead with the nuclear test," he told AFP.

Nam said Pak and Hyon are deputy chiefs of the politburo of the Korean People's Army (KPA) and Lee is its deputy operations bureau chief.

The North's official statement announcing the test clearly showed it was designed to please the military, which under a Songun (army-first) policy gets the best of everything in the impoverished state.

"It (the test) marks a historic event as it greatly encouraged and pleased the KPA and people that have wished to have powerful self-reliant defence capability," read the statement.

Koh Yu-Hwan, another North Korean expert and professor at Dongkuk University, said "only a handful of people" must have been involved in the test but admitted difficulty in pinpointing who they were.

"Kim, holding absolute power up there, seemed to side with the hardline military rationale that if North Korea conceded to US pressure once, it would keep conceding," Koh said.

"The North Korean leader may have had difficulty denying his own-created Songun policy in the face of pressure from hardliners."

The United States had increased pressure on North Korea to frustrate its nuclear ambitions but this served as justification for Kim to side with the hardliners, Koh said.

"The ultra-strong measure was taken according to Kim's belief that the US pressure had already become unendurable."

Koh forecast that the North's diplomats, who advocate negotiation, would have little room to maneuver for the time being due to the hardliners.

One measure said to have especially hurt the leadership was US financial sanctions on a Macau bank accused of laundering money from counterfeiting and other illegal activities.

North Korea has refused to return to six-party disarmament talks unless the United States lifts the sanctions.

Hong Kong-based security consultancy International Risk said in a report last week that Kim would not easily collapse, having "made strenuous efforts to build up his power base within the military."

It said the military had been well-fed and well-equipped despite general economic hardship in North Korea since the end of the Cold War, with a drastic cut-off in economic assistance from the former communist bloc.

The consultancy said that while interactions with the world in recent years have ostensibly been handled by Kim and the country's diplomats, "the hardline policy approach that Pyongyang took shows the heavy hand of the generals who have been opposed to negotiating away the country's nuclear weapons capability."

International Risk said the nuclear test "suggests that the generals' patience for diplomacy has come to an end and they are now keen to chart a new course in which the overriding goal is to build up the country's strategic nuclear and missile capabilities and ensure that they can become operational as quickly as possible. "This will likely mean more and perhaps frequent nuclear and missile tests in the coming months."

earlier related report
North Korea Faces Growing US Nuclear Threat Claims Pyongyang
Seoul (AFP) Oct 16 - North Korea is under growing threat of nuclear attack from the United States, the Stalinist regime's number two said Monday, urging its impoverished citizens to brace for "final victory". Kim Yong-Nam also said the people and the army of the Democratic People's Republic of Korea (DPRK) were happy that its successful October 9 nuclear test had enhanced the self-defence capacity of the reclusive state.

"The security of our socialist country is seriously threatened by the daily-growing threat of a nuclear war from the US and its vicious moves to isolate and stifle DPRK," Kim said in a speech carried by the (North) Korean Central Television Station.

North Koreans should brace themselves for more tension with the US, but the state would "certainly achieve a final victory in the historic stand-off with the US," Kim said in a 15-minute speech monitored by South Korea's Yonhap news agency in Seoul.

His comments come little more than 48 hours after the United Nations Security Council voted unanimously to impose tough new sanctions on Pyongyang for defying international calls not to go ahead with the test.

It was a defiant message from Kim, who was speaking on the occasion of the 80th anniversary of the Down-with-Imperialism Union at Pyongyang's Indoor Stadium.

"A recent successful underground nuclear test in the DPRK with its indigenous wisdom and technology 100 percent will contribute to preserving peace and stability on the peninsula," he said, according to Yonhap.

"It marked an historic event that greatly encouraged and pleased the army and people of the DPRK who have desired to have a powerful self-reliant national defence capacity.

The situation on the Korean peninsula required the army and people of North Korea to "wage a dynamic struggle ... under the banner of independence against imperialism," he added.

Pyongyang has yet to give an official reaction to a UN resolution passed unanimously on Saturday, which calls on the North to give up all weapons of mass destruction and allows nations to stop cargo going in and out of North Korea to prevent any illicit trafficking.

The measure also bars heavy conventional weapons and luxury goods from being sent to North Korea, calls for a freeze in any funds connected with the North's WMD programmes, and urges it to return to disarmament talks.

North Korea said earlier this month that it had to conduct a nuclear test in response to US sanctions and what it called the threat of a nuclear war from the United States.

The United States last year imposed sanctions on a Macau bank which it accused of laundering North Korean money and helping to distribute very high quality counterfeit US currency.

The UN's nuclear watchdog, the International Atomic Energy Agency, meanwhile said Monday it could not confirm the North had even carried out an atomic weapons test.

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