South Korea will start receiving advanced surveillance planes from US aircraft giant Boeing this year, officials said Wednesday.

The first of the modified Boeing 737 Airborne Early Warning and Control (AEW&C) planes will be delivered to South Korea's air force in July, a defence ministry spokesman said.

It has successfully completed test flights and is now in the final stage of evaluation, he said.

The remaining three being built under a 1.6 billion dollar deal in 2006 will be delivered by the end of 2012, he said.

Military officials said the planes would strengthen Seoul's capacity to carry out air surveillance of North Korea.

South Korea currently has no high-altitude air surveillance system of its own and depends on US airborne reconnaissance aircraft based at Okinawa in Japan.

The AEW&C encompasses a variety of aircraft control and advanced radar systems that can track airborne and maritime targets simultaneously, and direct fighter jets and ships to engage them.

It has an operational ceiling of 12,400 meters (41,000 feet) and can carry two pilots and up to 10 mission crew.