At a semi-annual arms control meeting in Tokyo, Japanese and US officials reiterated the need for tighter expert-level cooperation to ensure North Korea drops its nuclear ambitions, said a Japanese diplomat who attended the half-day session.

US Undersecretary of State for Arms Control and International Security John Bolton, who headed the US delegation, told the meeting that North Korea would only benefit by disarming itself, according to the Japanese diplomat.

Bolton cited the example of Libya, which agreed in December to dismantle the country's nuclear, chemical and biological warfare programs and renounce the pursuit of such weapons.

In return, Washington lifted most sanctions against Tripoli in April.

Bolton made the same comment in a brief meeting Friday with Japanese Foreign Minister Yoriko Kawaguchi, telling her that "the international community must continue to call on North Korea" to disarm, the diplomat said.

This was an echo of his remarks Wednesday in Seoul, where he met his South Korean counterparts.

Bolton also told the Tokyo meeting that Iran must cooperate with the International Atomic Energy Agency (IAEA), which has conducted more than a year of inspections related to suspicions it is seeking to develop a nuclear bomb under cover of its efforts to generate nuclear power.

Iran has been the subject of a string of IAEA resolutions criticising its level of cooperation with the IAEA.

Japan also reiterated at the meeting that Washington should ratify the Comprehensive Nuclear-Test-Ban Treaty and expressed its concerns over US research on so-called mini-nuke small nuclear weapons, the Japanese diplomat said.

WAR.WIRE