Pyongyang, Oct 9 (IANS): North Korea said Tuesday that the US is within the target range of its strategic rocket forces, the official KCNA news agency reported.

A spokesperson for the National Defense Commission of North Korea announced that the country is equipped with strategic rocket forces and is now able to place the US, South Korea, Japan and Guam within its target range, reported Xinhua.

"We are well prepared to fight with nuclear (weapons) against any nuclear (attacks) by the US and its followers," said the spokesman, vowing to launch all-out efforts to match the US and South Korea.

"Nuclear for nuclear, missile for missile," he said.

The spokesperson criticised the US ambition "to lay strategic siege network to Asia", adding that Pyongyang "will show the real bitterness of a war that the world has never known or imagined".

The announcement came after the South Korean presidential office said Sunday that under a revised pact with the US, Seoul planned to develop ballistic missiles with a range of 800 km, which could cover the entire peninsula, as part of its efforts to better respond to perceived missile threats from North Korea.

Critics said South Korea's extension plan ran counter to its commitment as a member of the global arms control agreement, known as the Missile Technology Control Regime (MTCR), an informal association that aims at curtailing the spread of unmanned delivery systems that could deliver weapons of mass destruction.

However, the White House Sunday defended South Korea's pursuit of longer-range missiles.