金正恩童年照曝光

Rare new photographs of Kim Jong-un as a young boy have emerged during a concert for the North Korean air force.

Pictures showing the 31-year-old North Koreanleader as a chubby toddler, saluting while in uniform, were shown on KCTV, the country's state broadcaster.

Other photographs showed him first as a young boy, then as a rotund teenager, at the controls of an aeroplane.

Until now, only a handful of pictures of Kim as a young boy have been seen, one showing him with his mother, Ko Yong-hui, and one a seeming passport picture, in which he has a bowl haircut.

Only one photograph is known to exist from his days as a student, which shows him on what appears to be a school trip with fellow pupils at the International School of Berne, in Switzerland.

Kim kept his identity secret from students and teachers. Using name of Pak Un, Swiss authorities were told that Kim was the son of an employee at North Korea’s embassy when he enrolled in August 1998.

Friends have said he was “obsessed” with basketball and showed “absolutely no interest” in politics.

As the photographs emerged, South Korea warned that the North could be planning a fourth nuclear test to ramp up tensions ahead of President Obama's upcoming visit to Seoul.

"Our military is currently detecting a lot of activity in and around the Punggye-ri nuclear test site," said Kim Min-seok, a spokesman for the Defence ministry.