White House officials said Monday North Korea's threat of another nuclear test will do little to change Washington's approach toward the communist regime, as it only demonstrates lack of its willingness for meaningful talks.

They said North Korea should discontinue a pattern of provocative steps if it wants dialogue.

"Given the recent North Korean statements threatening new type of nuclear tests, new type of missile tests, it's clear that North Korea is not signaling any interest in what we would consider to be credible and authentic negotiations," Evan Medeiros, Obama's key aide on Asia policy, said at a Foreign Press Center briefing here. "In that context, you know, we're looking for some sign they're actually committed to denuclearization."

He was referring to efforts to restart the six-party talks on Pyongyang's nuclear program. Last held in December 2008, the negotiations also involve South Korea, China, Japan and Russia.

Speculation is rampant over whether or when the unpredictable North will carry out what would be its fourth-known nuclear test.

Pyongyang openly said it may press ahead with a "new type" of nuclear test, with President Barack Obama due in the region later this week. He will travel to Seoul and Tokyo, followed by trips to Malaysia and the Philippines.

North Korea has increased activities at its underground nuclear test site, including more movement of vehicles, according to South Korean military sources.

During his trip to the region, Obama will try to reassure Washington's security commitment to its allies there in the face of growing North Korean threats, Ben Rhodes, deputy national security adviser for strategic communication said, speaking alongside Medeiros.

"We would never close the door to diplomacy, and we're willing to pursue those types of negotiations but only if they're based on North Korea demonstrating that it's prepared to keep its commitments," he added.

The White House would not publicly discuss intelligence-related reports of what's going on at the North's nuclear test site.

"Obviously we monitor that kind of activity very closely and we note a pattern of provocative actions from the regime and the DPRK that has been consistent, unfortunately, for many years, but I don't have anything specific on those reports," White House Press Secretary Jay Carney said at his daily press briefing. (Yonhap)