The Patriots would replace South Korea's ageing ground-to-air Nike missiles, which were introduced 40 years ago.

"It would be the first Patriot missile system of our own," a DAPA official told AFP.

The United States, which has 29,500 troops stationed here, has eight batteries of Patriot missiles at four air bases throughout South Korea.

The South Korean military had planned to buy 48 Patriots from the United States in 2000, but the plan was scrapped because of a dispute over the cost.

The DAPA said it was seeking to buy an undisclosed number of second-hand Patriot missiles which are being put out of service in the course of the restructuring of the German armed forces.

It also wants ground control equipment for the systems from the United States.

A member of South Korea's National Assembly Defense Committee was quoted as telling Yonhap news agency that the new missile defense system was expected to be introduced as early as next year for deployment in 2008.

"I understand the new Patriot missile system would consist of a battalion-size unit," the legislator said, requesting anonymity.

A Patriot battalion is usually made up of three battery units, each of which carries eight missile launchers and a command center, according to military officials.

The announcement comes amid tensions over North Korea's firing of seven missiles in July in defiance of warnings from the international community.

Military experts say North Korea's missile development poses a major threat to regional security.

Related Links
Learn about missile defense at SpaceWar.com