North Korea is one of the most heavily militarised countries in the world. Its one million strong army is considered to be the world's fifth largest.

Military spending accounts for some 25% of GDP, according to US estimates, while some 40 out of every 1,000 North Koreans are enlisted in the armed forces, compared to 14 out of every 1,000 South Koreans.

Most military equipment is derived from Chinese and Russian designs. Analysts consider North Korea's tanks, aircraft and ships to be relatively obsolete in comparison to modern Western forces however.

In recent years the country has pursued an ambitious missile building programme in tandem with efforts to build nuclear weapons.

North Korea possesses a number of ballistic missiles with varying ranges. Currently none are thought to be able to travel more than about 800km. Missile testing has been sporadic, and in many cases, has appeared unsuccessful.

The testing of a small nuclear device in October 2006 alarmed the international community and triggered UN sanctions.

However North Korea is thought to be some way from possessing the technology required to miniaturise and deliver a nuclear warhead via a missile.