South Korea on Thursday released a photo of Pyongyang taken from one of its own satellites after North Korea published imagery of Seoul using what it claimed was a military spy satellite.

The color photo, taken with "land satellite No. 1," clearly shows Kim Il-sung Square and its surrounding facilities, including a history museum, an art museum and a department store.

By contrast, the North Korean photo released Monday was in black and white, and barely showed the outlines of bridges across the Han River and a port in the western city of Incheon.

The North's Korean Central News Agency said the camera fitted on the "test-piece satellite" built for military reconnaissance purposes had a resolution of 20 meters.

Experts here said a reconnaissance satellite must have a resolution of at least 0.5m, making the North's equipment impossible to use for its stated purpose. (Yonhap)