The United States urged North Korea on Monday to abide by its international obligations and give up its nuclear program after Pyongyang's top envoy to London warned that the communist nation is prepared to fire nuclear missiles.

The North's ambassador, Hyon Hak-bong, made the remark in an interview with Sky News, saying, "It is not the United States that has a monopoly on nuclear weapons strikes" and the North would launch a nuclear attack only in the event of an American first strike.

"I saw those reports," State Department deputy spokeswoman Marie Harf said at a regular briefing. "There's obviously an overwhelming international consensus against North Korea's nuclear and ballistic missile programs. We have called on North Korea to abandon both programs in a complete verifiable and irreversible manner."

"This is required by multiple U.N. Security Council resolutions and we remain fully prepared to deter, defend against and respond to the threat posed by North Korea. Obviously, we're steadfast in our commitment to the defense of not only the United States but our allies and our interests in the region," she said.

Asked for comment on the North's claim it has nuclear weapons, Harf said it is no secret.

"There's a reason we're working to denuclearize the Korean Peninsula," she added. (Yonhap)