For the purpose of protecting from danger traffic along a highway which consists of or comprises a made-up carriageway, or of making the crossing of it less dangerous to pedestrians, the highway authority for the highway may construct, light and maintain subways under the highway for the use of pedestrians, and may alter, remove or close temporarily any such subway.
With respect to highways in Greater London, the powers of a highway authority under subsection (1) above may be exercised with that authority's consent—
Subsection (1) above has effect in relation to a road which consists of or comprises a made-up carriageway and to which the public have access, but which is not a highway, as if it were a highway and as if the council of the district or London borough in which the road is situated were the highway authority for it or, in the case of a road situated in the City, as if the Common Council were the highway authority for it or, in the case of a road in Wales, as if the Welsh council in whose area it is situated were the highway authortiy for it.