A U.S. special envoy warned North Korea Wednesday against "any provocations" as the unpredictable communist country hinted at conducting a nuclear test in response to a U.N. Security Council resolution that penalized it for its December rocket launch.

"We think that would be a mistake," Glyn Davies, the U.S. special envoy on North Korea policy, told reporters when asked about the possibility of a North Korean nuclear test. "Obviously, we call on North Korea, as a member of the international community, not to engage any provocations."

Davies arrived in Seoul earlier in the day as part of his three-nation Asian trip that will also take him to Beijing and Tokyo. His Asian trip had been scheduled long before the U.N. Security Council took the action.

Davies called on North Korea to abide by the U.N. resolution, which he said sent a "strong signal" to the communist country.

"That is up to North Korea," he said, urging Pyongyang to "live up to these obligations, live up to commitments and choose the path of peace and prosperity."

In its resolution adopted Wednesday, the U.N. Security Council ordered new sanctions against North Korea, vowing to take "significant action" if the country carries out another rocket launch or a nuclear test.

In Seoul, Davies is set to meet with South Korea's chief nuclear envoy Lim Sung-nam on Thursday.

Earlier in the day, a senior Seoul diplomat said Seoul and Washington are considering slapping "additional sanctions" on North Korea, separated from the ones specified in the U.N. resolution.

The additional sanctions will be one of the topics of the Davies-Lim   meeting, the diplomat said, speaking on condition of anonymity.

"We have been in discussions with the U.S. side about additional bilateral sanctions against the North following the U.N. resolution," the diplomat said.

Possible options would include making it more difficult for North Korean ships to travel in waters near the Korean Peninsula and strengthening inspections of North Korean ships suspected of engaging in weapons trafficking in accordance with U.N. sanctions, the diplomat said.

South Korea has also been "in negotiations with other relevant countries about additional bilateral sanctions against North Korea," the diplomat said.

In a swift response to the U.N. resolution, North Korea's foreign ministry threatened to strengthen its "nuclear deterrence," in an indication that it could conduct another nuclear test.

The diplomat said South Korea has been monitoring activities at a possible nuclear site in North Korea to determine if the North's third nuclear test is imminent, but said that "so far there has been no imminent sign of a nuclear test," adding that they are taking precautions and will be prepared to deal with all possible situations.

North Korea has been under U.N. sanctions since 2006 when it conducted its first nuclear test. The sanctions were tightened in 2009 after its second nuclear test.

Also on Wednesday, Seoul's foreign ministry spokesman Cho Tai-young said South Korea will "review bilateral measures against North Korea with relevant countries while focusing on implementing the U.N. resolution."

Cho labeled the North's indication of a nuclear test as "very regrettable," while South Korea is closely monitoring activities at the North's nuclear test sites.

The spokesman also ruled out a meeting between Davies and South Korean President-elect Park Geun-hye. (Yonhap News)