The Pakistan Atomic Energy Commission says the country's two plants both observe international safeguards which prevent irradiated fuel from being used in nuclear weapons development.

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The irradiated fuel can then be unloaded from the reactor, the U-233 separated from the thorium, and fed back into another reactor as part of a closed fuel cycle.

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Once the MOX fuel assemblies have been irradiated in commercial power reactors, the plutonium can no longer be readily used for nuclear weapons.

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