Barack Obama may have a very big problem on his first day as President: North Korea threatens South with war.

On Saturday, a dour man in military uniform appeared on North Korean television, flanked by army flags, and read a statement saying the country was now on a war-footing. He said the North would take an “all-out confrontational posture” against its neighbour.

Although North Korea regularly issues threats against the South, a spokesman for the South Korea Unification ministry said it was the most serious threat since 1998.