Subject to subsection (2) below, in sections 11 and 12 of this Act “the appropriate Minister” means, in relation to any matter, the Minister in charge of any Government department concerned with that matter or, where more than one such department is concerned with that matter, the Ministers in charge of those departments, acting jointly.

Where the Commissioners of Customs and Excise or the Forestry Commissioners are concerned with any matter (whether alone or together with any other Government department) subsection (1) above shall apply as if the references to the Minister or Ministers in charge of any Government department or departments concerned with that matter were or included references to those Commissioners.

The validity of any order purporting to be made under section 11 of this Act shall not be affected by any question whether or not the order fell by virtue of subsection (1) above to be made by the Minister or department (or any of the Ministers or departments) purporting to make it.

In sections 11 and 12 of this Act “controls” means prohibitions, restrictions or requirements of any description, and any reference to the exercise of controls is a reference to the exercise or performance of any functions conferred or imposed by any enactment, or otherwise under any lawful authority, for or in connection with the enforcement of prohibitions, restrictions or requirements of any description.

For the purposes of those sections a train is engaged on an international service at any time when the whole or any part of the train is being used in the operation of such a service and a place is an authorised terminal control point for international services if it is designated as such in accordance with the international arrangements.

In those sections and this section—

• “the international arrangements” includes any agreements or arrangements between Her Majesty’s Government in the United Kingdom and the Government of any country on the Continent of Europe other than France which for the time being apply for regulating any matters arising out of or connected with the operation of international services; and

• “international service” means any service (including a shuttle service) for the carriage of passengers or goods by way of the tunnel system.