(1)A joint local-London charging scheme may only be made in respect of—
(a)roads for which the non-metropolitan local traffic authority, or any of the non-metropolitan local traffic authorities, by which it is made are the traffic authority, and
(b)roads in respect of which the London traffic authority, or any of the London traffic authorities, by which it is made may impose charges by a scheme under Schedule 23 to the [1999 c. 29.] Greater London Authority Act 1999 without the consent of the Secretary of State.
(2)A joint local-London charging scheme may only be made if it appears desirable for the purpose of directly or indirectly facilitating the achievement of—
(a)policies in the local transport plan of the non-metropolitan local traffic authority, or the local transport plans of the non-metropolitan local traffic authorities, by which it is made, and
(b)policies and proposals set out in the transport strategy prepared and published by the Mayor of London under section 142 of the [1999 c. 29.] Greater London Authority Act 1999.