(1) The Secretary of State may by regulations designate an area outside the United Kingdom as a designated area for the purposes of section 58B if the following condition is met.
(2) The condition is that the Secretary of State is satisfied that it is necessary, for the purpose of protecting members of the public from a risk of terrorism, to restrict United Kingdom nationals and United Kingdom residents from entering, or remaining in, the area.
(3) The reference in subsection (2) to the public includes a reference to the public of a country other than the United Kingdom.
(4) Where an area is designated by regulations under this section, the Secretary of State must -
(a) keep under review whether the condition in subsection (2) continues to be met in relation to the area, and
(b) if the Secretary of State determines that the condition is no longer met, revoke the regulations (or revoke them so far as they have effect in relation to that area if the regulations designate more than one ar
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