Kim Jong-un 'not ready' to lead North Korea

North Korean leader Kim Jong-il has died at the age of 69, state-run television has announced.

His designated successor is believed to be his third son, Kim Jong-un, who is thought to be in his late 20s.

However former US Assistant Secretary of State Christopher Hill, who led the delegation of the six-party nuclear talks on North Korea, said he believed Kim Jong-un was ''not ready'' to take the helm.