The United States said Monday it will judge North Korea "by its actions, not its words" after the communist nation's leader, Kim Jong-un, pledged efforts to improve inter-Korean ties in his New Year's message.

Kim said in the Jan. 1 address that the North will "make aggressive efforts to hold talks and improve relations" with South Korea, saying the country is willing to have talks in an open-minded manner with anyone who wants peace and unification.

"As we have long said, we support improved inter-Korean relations. However, North Korea will be judged by its actions, not its words," said Ory Abramowicz, a spokesperson for the State Department's Bureau of East Asian and Pacific Affairs.

"We continue to call on North Korea to refrain from actions that raise tensions in the region and focus instead on taking concrete steps toward fulfilling its international commitments and obligations," the official said.

Relations between the two Koreas showed signs of improvement as they reached a peace agreement in August that defused a tense military standoff, including an exchange of artillery fire across one of the world's most heavily fortified borders.

Under the agreement, the sides held a round of reunions of separated families in late October. But last month's high-level reconciliation talks ended without any agreement as the two sides remained wide apart on key contentious issues. (Yonhap)