Section 9A(3)(a) of the Building Societies Act 1986 (c.53) prohibits a building society, or a subsidiary undertaking of a building society, from trading in currencies where the amount or value of the consideration given by the society or undertaking exceeds £100,000. This Order increases that amount or value to £3 million.
Link: The Building Societies (Restricted Transactions) (Amendment to the Limit on the Trade in Currencies) Order 2017
Source: Legislation .gov.uk