North Korea has accused the United States of triggering a regional arms race by deploying navy destroyers equipped with Aegis missile tracking systems in the sea off the communist state.
A foreign ministry spokesman told the official Korean Central News Agency late Saturday the US build-up targeted China and Russia as well as North Korea.
US Navy Secretary Gordon England confirmed this month the deployment of Aegis-equipped destroyers in the Sea of Japan (East Sea) near North Korea, whose missile and nuclear programmes put it at the top of the US threat list.
The new US reinforcement "is a very dangerous provocation upsetting stability and strategic balance in Northeast Asia and sparking off an arms race in the region," the Pyongyang spokesman said in an interview monitored here.
"The adventurous missile defence system which the United States seeks to establish with Japan and South Korea involved is designed to contain China and Russia in the end."
He said North Korea "has taken to steadily increase all its means for self-defence including the nuclear deterrent force" against the United States.
The Aegis destroyers, a key part of the US missile defence system, are designed to track and intercept incoming enemy missiles after they have been detected by early warning radars.
North Korea has short-range Scud missiles largely targeting South Korea and Rodong missiles with a range of 1,300 kilometres (812 miles) which can hit most areas in Japan.
Pyongyang stunned the world in August 1998 by test-firing over Japan a Taepodong-1 missile with a range of up to 2,000 kilometres, claiming it was a satellite launch.
But North Korea declared a moratorium on missile tests in September 1999 under US-led international pressure and in May 2001 extended the decision until 2003.
The cash-strapped country has, however, refused to stop exports of missile technology, a major source of hard currency earnings. Washington has denounced Pyongyang as a leading global proliferator of weapons of mass destruction.
North Korea is locked in a stand-off with the United States and its allies demanding the communist regime scrap its nuclear weapons programmes.
Facing North Korean threats, South Korea has deployed new longer-range missiles capable of hitting most strategic targets in North Korea, the Maeil business daily said Saturday.