Road Traffic (Traffic and Parking) Regulations 1997
Reversing
12. (1) Before reversing, a driver shall ensure that to so reverse would not endanger other traffic or pedestrians.
(2) A driver shall not reverse onto a major road from another road.
(3) A driver shall not reverse from a place adjacent to a public road onto a public road save where it is clear to the driver that to so reverse would not endanger other traffic or pedestrians.