SEOUL, South Korea -- Suspicious Asian nations bristling with nuclear weapons, each striving for an nuclear war chest bigger than their neighbor's -- Washington's latest worry about North Korea reads like a Cold War flashback.

Vice President Dick Cheney raised the specter this weekend, saying a nuclear-armed North Korea could incite neighboring nations to build their own bombs.

Such an Asian arms race could spill over from Tokyo to Beijing and put some of the world's most populous areas in the shadow of nuclear weapons. Some could even end up being possessed by previously reluctant powers like South Korea or Taiwan.

Analysts admit that's unlikely to happen soon but warn it could erupt if Pyongyang keeps pursuing nuclear weapons.

"There's a very high likelihood that North Korea's possession of nuclear weapons will trigger an arms race in East Asia," said Paik Haksoon, a North Korea expert with the Sejong Institute, a foreign relations think tank outside Seoul.

'Not in China's interest'

Cheney's scenario begins with a nervous Japan considering the nuclear option in response to North Korea, and thereby firing the ire of Beijing.

"The idea of a nuclear-armed North Korea with ballistic missiles to deliver those will, I think, probably set off an arms race in that part of the world," Cheney said while appearing on NBC's "Meet the Press" in Washington.

"And others, perhaps Japan, for example, may be forced to consider whether or not they want to readdress the nuclear question. That's not in China's interest," Cheney said.

North Korea's nuclear ambitions have been the focus of an intensifying international standoff since October, when the United States said Pyongyang admitted to having a secret atomic weapons program in violation of a 1994 agreement.

Washington believes North Korea already has one or two nuclear weapons, and the country can process the raw material for several more in a matter of months.

Of particular concern is the possibility of North Korea mounting bombs atop missiles aimed at Seoul or Tokyo. While the North's ability to deliver a warhead this way is in doubt and the accuracy of its missiles suspect, the communist nation shocked the world in 1998 by firing a long-range ballistic missile over Japan into the Pacific Ocean.

Just last month, Japan's Defense Agency admitted that Tokyo considered developing its own nuclear arsenal in 1995 to counter the threat of a nuclear-armed North Korea. But Tokyo ultimately rejected the idea.

Paik said a nuclear Japan would likely trigger a domino effect, with China buttressing its own arsenal of an estimated 410 warheads. Pointing to its nuclear-armed neighbors and the potential increased threat from Beijing, Taiwan would then feel justified in joining the nuclear club, he said.

So far, Japan's post-World War II pacifist constitution has kept its overseas striking capability in check, said Toshiyuki Shikata, a former general in Japan's military.

Japan has no aircraft carriers, bombers or long-range missiles to project force. And as the only nation attacked by nuclear weapons, by the United States at the end of World War II, there is ingrained abhorrence of possessing atomic bombs.

But building them would not take long.

Japan has approximately 72 tons of plutonium in spent fuel rods from its nuclear power plants, according to 1999 figures of the International Atomic Energy Commission. North Korea, by contrast, is believed to possess no more than 66 pounds.

Both South Korea and Japan have largely relied on the U.S. nuclear umbrella as insurance against attack. But when faced with the verified presence of atomic bombs on the other side of the border, South Korea may consider arming itself, Paik said.

"It is not enough for South Korea to simply rely on the United States," he said. "They may not always be able to deter an attack or protect us."

For the time being, South Korea is a signatory to an international treaty that prohibits it from making nuclear weapons. But in the 1970s, Seoul had its own atomic program.

Fearful of a nuclear arms race in the region, however, the United States forced then-dictator Park Chung-hee to drop the plan, partly by threatening economic penalties for a nation that was then poor and still recovering from the 1950-53 Korean War.

In 1991, U.S. tactical nuclear weapons were removed from South Korea as part of arms reductions following the Cold War, according to South Korean defense experts. In the same year, the two Koreas signed a joint declaration pledging not to deploy, develop or possess atomic bombs on the peninsula.

Cheney said he would travel to the region next month to stress the need for North Korea's neighbors to help defuse the crisis.