(1)The interception of a communication in the course of its transmission by means of a telecommunication system is authorised by this section if conditions A to D are met.
(2)Condition A is that the interception—
(a)is carried out by or on behalf of a telecommunications operator, and
(b)relates to the use of a telecommunications service provided by the telecommunications operator.
(3)Condition B is that the interception is carried out in response to a request made in accordance with a relevant international agreement by the competent authorities of a country or territory outside the United Kingdom.
In this subsection “relevant international agreement” means an international agreement to which the United Kingdom is a party and which is designated as a relevant international agreement by regulations made by the Secretary of State.
(4)Condition C is that the interception is carried out for the purpose of obtaining information about the communications of an individual—
(a)who is outside the United Kingdom, or
(b)who each of the following persons believes is outside the United Kingdom—
(i)the person making the request;
(ii)the person carrying out the interception.
(5)Condition D is that any further conditions specified in regulations made by the Secretary of State for the purposes of this section are met.