Turning from a one-way road and parallel streams of traffic

Select the lane appropriate for the intended direction and signal both the lane change and the turn in good time. When traffic is moving in parallel streams, a driver may change lane to prepare for a turn, but must not cause danger or obstruction and cannot assume that any lane is suitable. Parallel streams are permitted when directed by traffic officers, on approaches to junctions controlled by officers or traffic lights, and in heavy traffic on roads with several lanes in each direction. They are not permitted in every urban situation, but a single carriageway does not by itself prohibit them. A driver continuing in the left lane must not leave the left indicator on, and motorcyclists may not pass between vehicles travelling side by side.