Basil Jet :
At the crossroads of Exhibition Road and Cromwell Road SW7, traffic
approaching from three directions is now banned from turning left or
right. This is signified by the green light being a forward arrow. At
other junctions where both turns are banned you would see a vertical
white arrow on a blue background beneath the three traffic lights, but
they have not done that here. The result is that if you arrive at the
junction when the light is red, you may not know that the turns are
banned until the light turns green, and since most people start moving
when the amber comes on, that seems a bit late to me.

What about cyclists? You can hardly expect them to wait for the green
light.

--
Mike Barnes