The defense chiefs of the United States and South Korea have agreed to hold trilateral talks with Japan to facilitate quick sharing of North Korean missile warning data.

US Defense Secretary Lloyd Austin met South Korean Defense Minister Lee Jong-sup in Seoul on Tuesday.

They exchanged views on how to deal with North Korea, which appears set to accelerate its nuclear and missile development programs.

According to a briefing after the talks, they strongly condemned North Korea's repeated launches of ballistic missiles. They also reaffirmed measures to enhance "extended deterrence," in which the US protects its allies with nuclear and other weapons.

They agreed to conduct joint simulation drills in February under the scenario of a nuclear threat by North Korea, and pledged to expand the scale of joint military drills.

The defense chiefs also agreed to hold working-level trilateral talks including Japan at the earliest opportunity, to discuss their security cooperation.

Austin told reporters that the US commitment to defending South Korea is ironclad. He added that he wants to underscore that the trilateral cooperation will enhance all aspects of their security.