Seoul, Sep 3 (IANS): South Korean President Moon Jae-in on Sunday ordered all available diplomatic efforts to completely isolate North Korea after Pyongyang's sixth nuclear test earlier in the day.

Moon convened an emergency National Security Council (NSC) meeting, which lasted for one-and-half hours from 1.30 p.m. (local time), according to the presidential Blue House.

The meeting was called to discuss countermeasures following Pyongyang's test of what it claimed was a hydrogen bomb that can be loaded onto a ballistic missile with intercontinental capabilities, Xinhua news agency reported.

During the NSC meeting, President Moon instructed high-ranking cabinet members and senior secretaries in charge of foreign affairs, security and defence to draw up the strongest punishment measures on North Korea in cooperation with the international community.

North Korea's state TV announced the country's test of the device meant for an intercontinental ballistic missile (ICBM) was a complete success.

North Korea's sixth nuclear detonation was officially confirmed by the Blue House during a press conference held by Chung Eui-yong, top national security advisor to President Moon.

Moon said all available diplomatic actions, including new UN Security Council resolution, should be considered to completely isolate North Korea in response to the its sixth nuclear device test.

The South Korean leader said his country would never tolerate an advancing technology of the North Korea's nuclear and missile programs, ordering the military to maintain a full defence readiness against further provocation.