The railway shall be constructed on a gauge of 1435 millimetres andthe motive power of the railway shall be diesel, diesel electric, steamor such other motive power as the Secretary of State may approve:

• Provided that nothing in this Order shall authorise the use ofelectrical power as motive power on the railway unless such power isobtained from storage batteries or from a source of generation entirelycontained in and carried along with the engines and carriages:

• Provided also that, if electrical power is used as motive power on the railway, such electrical power shall not be used in such a manner as to cause or be likely to cause any interference with any telecommunicationsapparatus (as defined in Schedule 2 to the Telecommunications Act 19847) or with telecommunications by means of such apparatus.