The interests of national security are specified in this section.

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The Secretary of State may by order modify this section for the purpose of specifying in this section a new consideration or removing or amending any consideration which is for the time being specified in this section.

An order under this section may apply in relation to cases under consideration by the F2CMA, F3by the Secretary of State or by the appropriate Minister (other than the Secretary of State acting alone) F4... before the making of the order as well as cases under consideration on or after the making of the order.