"The study of the recent policy clarified by (US) high-ranking officials... clearly suggests that the US 'landmark proposal' was nothing but a sham offer," a spokesman for the Stalinist state's foreign ministry said.

"The US is foolish enough to calculate that such mode imposed upon Libya would be accepted by the DPRK (North Korea) too," the spokesman told Pyongyang's official Korean Central News Agency (KCNA).

Senior US officials have urged North Korea to follow the example of Libya, which renounced the pursuit of its nuclear, chemical, and biological weapons plans. In return, Washington lifted most sanctions against Tripoli.

But Pyongyang has demanded rewards for the freezing of nuclear weapons programs as a first step which it says would lead to the eventual dismantling of its nuclear facilities.

Top US arms control official John Bolton, on a visit to South Korea this week, however, rejected the North's "freeze-to-reward" offer, calling for the immediate dismantling of its nuclear program.

"The DPRK, therefore, considers the US 'landmark proposal' to be little worthy to be discussed any longer," the North Korean spokesman said.

Pyongyang's reaction came after six-nation talks on the nuclear standoff ended in Beijing last month with the United States making a concrete offer to resolve the issue for the first time.

The US offer says that North Korea should be allowed three months to shut down and seal its nuclear weapons facilities in return for major economic and diplomatic rewards.

Pyongyang said in a foreign ministry statement last month that the US-proposed timeframe "totally lacked scientific and realistic nature."

North Korea has demanded energy aid and a US security guarantee and also wants Washington to lift sanctions and remove the Stalinist state from its list of states sponsoring terrorism.

"Whether the US takes part in the project to make reward for the DPRK's nuclear freeze or not is the key to the settlement of the nuclear issue," the North's foreign ministry spokesman said.

The stand-off over North Korea's quest for nuclear weapons erupted in October 2002 when the United States accused Pyongyang of operating a nuclear weapons program based on enriched uranium, violating the 1994 nuclear freeze of its separate plutonium producing program.

Pyongyang has denied running the uranium-based program, but has again fired up its once-mothballed plutonium-based program.

Three rounds of six-way nuclear talks bringing together the United States, the two Koreas, China, Japan and Russia have been held in Beijing in an effort to resolve the impasse with a fourth round scheduled for September.

US intelligence authorities say North Korea is believed to possess at least one or two nuclear bombs.

Expelling International Atomic Energy Agency inspectors in 2002 and reactivating a nuclear reactor producing weapons-grade plutonium, North Korea declared in 2003 that it had finished reprocessing some 8,000 spent fuel rods.

The United States believes the rods could have produced enough fissile material for five or six additional nuclear weapons.

WAR.WIRE