The North's state-run television said late Thursday the revamp of US Patriot missiles in South Korea would "complete war preparations for preemptive strikes against North Korea," according to the South's main North Korea monitor Yonhap news agency.

"If the United States wants to resolve the nuclear problem peacefully, it must stop the war preparations and change its hostile policy on the DPRK (North Korea)," the television said in a commentary.

"The US arms buildup in South Korea is creating a stumbling block to resolving the nuclear problem as it is dangerous war preparation to increase tensions on the Korean peninsula."

US military authorities said Tuesday they had completed upgrading its Patriot missile batteries in South Korea as part of an 11-billion-dollar plan to beef up its deterrence against North Korea.

Equipment has been brought in to upgrade the US Patriot Advanced Capability-2 (PAC-2) to PAC-3 with enhanced capability to destroy ballistic missiles, cruise missiles and aircraft, according to a US army statement.

The PAC-3 system is part of the 11 billion dollar investment over several years to improve US defense capabilities on the Korean peninsula.

Around 37,000 US troops have been stationed in South Korea since the 1950-1953 Korean war to thwart North Korea's military threat.

The United States, China, Japan, Russia and the two Koreas met in Beijing last month to explore ways to resolve a stand-off over North Korea's suspected nuclear arms programs.

The six-nation talks ended without producing any tangible progress.

Delegates agreed to meet again but they failed to fix a date for the next round with the North terming the initial round as "useless".

SPACE.WIRE