In a statement issued through the official Korean Central News Agency, a North Korean foreign ministry spokesman added that Pyongyang would only return to the nuclear Non-Proliferation Treaty (NPT) it opted out of "if the Korean peninsula is denuclearized".

He said North Korea's peaceful nuclear program was "pertaining to its sovereignty and this should never be included in the objects to be frozen or dismantled".

At six-party talks in Beijing last month, the United States offered Pyongyang three months to shut down and seal its nuclear weapons facilities in return for economic and diplomatic rewards.

It was the first significant overture to Pyongyang since US President George W. Bush took office in early 2001 and branded the North part of an "axis of evil" alongside Iran and pre-war Iraq.

But Pyongyang has rejected the US plan as unrealistic.

On the issue of allowing its nuclear facilities to be inspected, the spokesman said it could only happen once the dismantlement of its nuclear programme had been agreed upon and begun.

"A freeze is the first phase leading to the final dismantlement of its nuclear program and the freeze is bound to be accompanied by an objective verification," he said, adding that by verification North Korea meant monitoring "the state of freeze".

"It is very illogical to argue about inspection from the phase of freeze. Moreover, any attempt to force the DPRK to accept it is nothing but a sinister attempt to disarm it," he argued.

North Korea has offered to freeze its nuclear weapons drive in return for an end to US sanctions and energy assistance. It has also urged Washington to come up with immediate rewards for a nuclear freeze.

Pyongyang will dismantle its nuclear weapons program "only when conditions for it are created" by the US dropping its hostile policy, the spokesman said.

"To this end, it wishes to wipe out mistrust and build confidence between the DPRK (North Korea) and the US by implementing the measure of 'reward for freeze' to begin with," he said.

The United States had insisted that North Korea had to scrap its nuclear ambitions first before it would receive concessions.

At the previous round of six-party talks in Beijing, however, Washington called for a step-by-step dismantling of North Korea's plutonium and uranium weapons programs.

North Korea has demanded energy aid and a security guarantee from the United States. Pyongyang also wants Washington to lift sanctions on North Korea and remove the Stalinist regime from the US list of states sponsoring terrorism.

WAR.WIRE