379. Defence or national security.

The Secretary of State1 may by direction exclude or restrict access by the public2 to any land during any period if he is satisfied that the exclusion or restriction of such access to the extent provided by the direction is necessary for the purposes of defence or national security3.

Such a direction may be expressed to have effect:


    (1)     during a period specified in the direction4;


    (2)     during a specified period in every calendar year5;


    (3)     during a period which is to be determined in accordance with the direction by a person authorised by the Secretary of State6, and notified