[cnn-photo-caption image=http://i2.cdn.turner.com/cnn/2009/WORLD/asiapcf/05/30/gates.north.korea/art.gates.afp.gi.jpg caption="Defense Secretary Robert Gates, left, meets with other world leaders at a conference Saturday in Singapore."]
(CNN) - The United States will not accept North Korea as a nuclear-armed state, Defense Secretary Robert Gates said Saturday at an international conference.
"We will not stand idly by as North Korea builds the capability to wreak destruction on any target in the region - or on us," said Gates, speaking at the International Institute for Strategic Studies in Singapore.
"Our goal is complete and verifiable denuclearization of the Korean Peninsula, and we will not accept North Korea as a nuclear weapons state," he said.
His comments came amid growing concern across the globe over North Korea's latest nuclear test and test-firings of short-range missiles.
On Friday, two Defense Department officials said the latest U.S. satellite imagery has spotted "vehicle activity" at a North Korean ballistic missile facility.
"North Korea's nuclear program and actions constitute a threat to regional peace and security. We unequivocally reaffirm our commitment to the defense of our allies in the region," Gates said in Singapore.