London's Register of roadworks has this:
Baylis Road - Excavate and remove kerb line. Relocate street furniture. Contruct new separated cycle lane. Install new traffic signals. Resurface carriageway.
Westminster bridge - Realigned kerb, footway renewal, c'way raised, rearranged signalised ped crossing.
Carlisle Lane / Upper Marsh - Repave footway and c'way to flush level, reverse direction of flow.
Seems to be part of some bigger changes to the area around Lambeth North Station to make it more cycle / pedestrian friendly.