South Korea's defence ministry has requested a budget worth 164 trillion won ($179 billion) from 2008-12, with the purchase of unmanned air vehicles, airborne early warning and control and fighter aircraft high on its list of priorities.

The plan calls for an annual budget increase of 9.6% during the five years, with the defence ministry's share of the nation's gross domestic product to rise from 2.7% this year to 3% in 2012. Dubbed the "mid-term defence plan", the proposal was established with an emphasis on "expanding war-deterrent capabilities", the ministry says.

A key element of the request is the Northrop Grumman RQ-4 Global Hawk high-altitude long-endurance UAV, which South Korea has previously requested from the USA, only to be rebuffed in 2005.

Strict controls mean the US Congress must approve any export of the aircraft, which is deemed to have highly sensitive equipment.

Seoul wants the aircraft to keep a closer watch on North Korea, and hopes to purchase four air vehicles by 2012, when it will take over wartime operational control of its military from the USA.

The budget will also be used to pay for four Boeing 737-based AEW&C aircraft. South Korea signed a $1.59 billion contract for the aircraft last November, with the first scheduled to be delivered in 2011 and the other three to follow in 2012.

South Korea is also in the process of buying another 20 fighters under a $2.5 billion deal. The Boeing F-15K is the only contender in the tender after other manufacturers declined to take part.

A contract could be signed around early 2008, with deliveries scheduled to take place in the 2010-12 timeframe.