The Secretary of State may by order provide that, as from such date as may be specified in the order, section 19 of this Act shall not apply to a dwelling the rateable value of which on such day as may be specified in the order exceeds such amount as may be so specified.
An order under this section—
(a) may be made so as to relate to the whole of England and Wales or to such area in England and Wales as may be specified in the order, and so as to apply generally or only to, or except to, such classes or descriptions of dwellings as may be specified in the order; and
(b) may contain such transitional provisions as appear to the Secretary of State to be desirable.
The power to make an order under this section shall be exercisable by statutory instrument and no such order shall have effect unless it is approved by a resolution of each House of Parliament.