The Secretary of State must take all necessary steps to—
ensure that an investigation is carried out, or
provide any other assistance or information,
if requested to do so by an approved third country competent authority ....
Where the request includes a request for the transfer of audit working papers and investigation reports, the Secretary of State must act in accordance with section 1253D.
Within 28 days following the date on which he receives the request, the Secretary of State must—
provide the assistance or information required by the requesting authority under subsection (1)(b), or
notify the requesting authority of the reasons why he has not done so.
But the Secretary of State need not take steps to comply with a request under subsection (1) if—
he considers that complying with the request may prejudice the sovereignty, security or public order of the United Kingdom;
legal proceedings have been brought in the United Kingdom (whether continuing or not) in relation to the persons and matters to which the request relates; or
disciplinary action has been taken by a recognised supervisory body in relation to the persons and matters to which the request relates.
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