The Republic of Korea has reached a landmark agreement with the United States to extend the range of Seoul's ballistic missiles by more than twice the current limit to counter the Democratic People's Republic of Korea, the government said on Sunday.

The move to significantly boost the ROK's missile capabilities along with development of advanced aerial reconnaissance vehicles is likely to rattle the DPRK.

It may also stoke concern in China, Japan and Russia, parts of which would be within range of the new missiles.