WASHINGTON (AFP) - North Korea remains a nuclear proliferation risk and is probably still pursuing a uranium enrichment capacity, a US intelligence assessment concluded Tuesday.

In an annual threat assessment to Congress, US national intelligence chief Mike McConnell noted that Pyongyang missed a December 21 deadline for making a full declaration of its nuclear program.

"The IC (intelligence community) continues to assess that North Korea has pursued a uranium enrichment capability at least in the past, with at least moderate confidence that the effort continues today," the report said.

In discussing proliferation risks, the report noted North Korean missile sales to Iran and several Middle Eastern countries.

"We remain concerned North Korea could proliferate nuclear weapons abroad," it said.

But the assessment said Pyongyang probably views its missile and nuclear capabilities "as being more for deterrence and coercive diplomacy than for warfighting and would consider using nuclear weapons only under certain narrow circumstances."

"We also assess that Pyongyang probably would not attempt to use nuclear weapons against US forces or territory unless it perceived the regime to be on the verge of military defeat and risked an irretrievable loss of control," it said.

A North Korean nuclear test in October 2006 supported previous US assessments that Pyongyang has produced nuclear weapons even though it produced a yield of less than one kiloton, the report said.

It said North Korea has produced enough plutonium for at least half a dozen weapons.

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