North Korea would possibly consider a nuclear strike if they thought they could survive the inevitable counter-strike, a former British ambassador to the country has said.
Speaking on BBC Radio 4's Today programme, John Everard said:
If they believe they can survive a nuclear counter-strike, the possibility that they may launch a nuclear first strike remains.
Pyongyang's claims that it has detonated a miniaturised hydrogen-bomb have been condemned resoundingly by the international community.
Some analysts suggest the device may have been between 6 and 12 kilotons - smaller in size than the atomic bomb dropped on Hiroshima by the US in 1945 (16kt).
A US military statement said the low-level flight over ally South Korea was in response to the North's 'recent provocative action'.
Tens of thousands of people danced and applauded in central Pyongyang, North Korea, in support of the country's reported H-bomb test.
Why is this latest development in North Korea's quest for nuclear power seen as potentially significant?