Kim Jong-un has appeared to suggest North Korea possesses a hydrogen bomb, in comments published on state media.
North Korea was “ready to detonate a self-reliant A-bomb and H-bomb”, KCNA quoted Kim Jong-un as saying.
If true, the development would mark a significant advancement in North Korean nuclear capabilities.
The North Korean leader made the remarks as he inspected a historical military site in the capital Pyongyang.
The work of his grandfather Kim Il-sung had turned North Korea into a “powerful nuclear weapons state ready to detonate a self-reliant A-bomb and H-bomb to reliably defend its sovereignty and the dignity of the nation”, Kim Jong-un is quoted as saying.
While North Korea has made previous claims about its nuclear weapons capabilities this is thought to be its first reference to an H-bomb.
Such devices use fusion to create a blast far more powerful than a more basic atomic bomb.
North Korea has carried out three underground nuclear tests before, but experts cast doubt over the latest suggestions.
Independent observers are rarely allowed access to the secretive communist state, making verifying the authorities’ claims difficult.