North Korea on Thursday denounced South Korea's plan to buy high-end fighter jets and surveillance drones from the United States, warning that it will escalate cross-border tensions and stimulate an arms race in the region.

South Korea is pushing to buy 40 Lockheed Martin-developed F-35A stealth fighter jets and four unmanned Hawk surveillance aircraft, called RQ-4 Block 30s, from the U.S. The plan is part of Seoul's mid-term force improvement program aimed at coping with growing military threats from North Korea.

In a statement issued through its party organization, the Committee for the Peaceful Reunification of the Fatherland, North Korea warned that the South Korean plan will have a negative impact on inter-Korean relations.

The statement was carried by the (North) Korean Central News Agency.

Relations between the countries have been up and down since May 2009 when the Lee Myung-bak government cut off aid and scrapped most forms of inter-Korean economic cooperation.

The North's statement was its first denunciation of the South since it announced its recent purge of Jang Song-thaek, the once powerful uncle of leader Kim Jong-un, on Monday.

(Yonhap News)