Secretary of Defense Robert Gates is warning North Korea, and pointedly not taking the military option off the table.

SINGAPORE (AP) — U.S. Defense Secretary Robert Gates warned North Korea on Saturday that the United States would respond quickly if moves by the communist government threaten America or its Asian allies.

“We will not stand idly by as North Korea builds the capability to wreak destruction on any target in the region — or on us,” Gates told an annual international meeting of defense and security officials from Asia and the Pacific Rim.

Gates called North Korea’s nuclear program a “harbinger of a dark future” but said he does not consider it a direct military threat to the United States “at this point.”