Subject to subsection (2) below a member of a body to which this section applies shall be entitled to receive payments by way of travelling allowance or subsistence allowance where expenditure on travelling (whether inside or outside the United Kingdom) or, as the case may be, on subsistence is necessarily incurred by him for the purpose of enabling him to perform any approved duty as a member of that body, being payments at rates determined by that body, but not exceeding, in the case of travel F1or subsistence for the purpose of an approved duty within the United Kingdom, such rates as may be specified by the Secretary of State.

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