A speed limit of 20mph has been imposed on all central London roads managed by Transport for London (TfL) in a bid to reduce road deaths.
All TfL roads within the Congestion Charging Zone (CCZ) are subject to the limit since 00:01 GMT on Monday.
Some critics said the speed limit would make no difference because traffic already moves so slowly in the area.
The Vision Zero scheme is a collaboration between the London mayor, TfL and the Metropolitan Police.
