A senior U.S. official has reaffirmed the United States' commitment to extended deterrence for South Korea.

Bonnie Jenkins, Under Secretary for Arms Control and International Security, issued the position on Wednesday during a press briefing on the Tenth Nuclear Non-Proliferation Treaty(NPT) Review Conference in New York.

When asked about concerns among South Koreans on the issue, Jenkins reiterated that Washington remains very committed to extended deterrence for its ally.

As for denuclearization of North Korea, the under secretary said that the U.S. administration has been very clear about its position that it is open to dialogue with the regime.

Jenkins said that if the North refuses to return to the NPT, it has to at least engage in dialogue, but the North's rejection of dialogue is restricting the U.S.' capabilities.