"And we have to deal with them. We have to be sober, calm, cool, collected about these periods. That's what we're doing right now," he said. "And we are assuring our South Korean allies day to day that we stand with them in the face of these provocations."
The recent saber-rattling from Pyongyang has included threats of pre-emptive nuclear strikes against the United States and South Korea, as well as the declaration that the armistice that stopped the Korean War in 1953 is null and void.
On Tuesday, the North said it planned to place military units tasked with targeting U.S. bases under combat-ready status.
Most observers say North Korea is still years away from having the technology to deliver a nuclear warhead on a missile, but it does have plenty of conventional military firepower, including medium-range ballistic missiles that can carry high explosives for hundreds of miles.
Little said Thursday that the United States was keeping a close eye on North Korea's missile capabilities.
"The important thing is for us to stay out ahead of what we think the North Korean threat is, especially from their missile program," he said. "They've been testing more missiles, and they've been growing their capabilities and we have to stay out ahead."