The United States and major powers including China must pressure North Korea to abandon its nuclear ambitions following worrying revelations about its uranium enrichment program, America’s top military officer said yesterday.

North Korean officials took a U.S. nuclear scientist, Siegfried Hecker of Stanford University, to a plant at its Yongbyon nuclear complex where he saw hundreds of centrifuges, said sources familiar with the matter.

Washington has believed since 2002 that Pyongyang had such a program but the apparent sophistication of its effort could ignite fresh debate over how to deal with North Korea’s unpredictable leadership and whether to resume talks aimed at ending its nuclear ambitions.

Adm. Mike Mullen, chairman of the U.S. military’s Joint Chiefs of Staff, said the disclosure showed that North Korea was a “dangerous country” intent on making nuclear weapons and major powers must work together to bring pressure on North Korean leader Kim Jong-il.

“We have to continue to bring pressure on him specifically. Those in the region — in particular the six-party talk countries, Russia, China, the United States, Japan, and South Korea, we all have to continue to do that,” Mullen told ABC television’s “This Week with Christiane Amanpour” talk show.

The North Koreans told Hecker they had 2,000 centrifuges in operation but the U.S. team that visited the country was unable to verify that they were working, the sources told Reuters.

What now?

U.S. nuclear scientist Siegfried Hecker of Stanford University addresses the options for dealing with North Korea:

» “A military attack is out of the question. Tightening sanctions further is likewise a dead end, particularly given the advances made in their nuclear program and the economic improvements ... in Pyongyang.”

» “The only hope appears to be engagement. The United States and its partners should respond to the latest nuclear developments so as to encourage Pyongyang to finally pursue nuclear electricity in lieu of the bomb.”