Three London borough councils have announced plans to merge services and create a “super council” in the west of the capital.

Hammersmith and Fulham, Kensington and Chelsea, and Westminster said the move, which involves planning, would save up to £100m a year.

The announcement follows a letter sent to councils on Wednesday by communities secretary asking English councils to share functions, such as planning.

Chief executives from the three councils will work up the plans over the next five months and report back in more detail about the proposals in February next year.

Working groups will be set up to examine  ways of merging environmental services, family services and corporate services.

Hammersmith and Fulham leader Stephen Greenhalgh said there would be “significant reductions” in staff.

In a joint statement, the leaders said: “Our chief executives will report back in February next year with recommendations for action before we then consider the next steps, while our staff and our partners will be fully consulted at every stage, with public engagement when firm plans emerge.

“We want to stress though that local priorities will still be driven by local people, and the democratic mandate rested in elected councillors such as ourselves, will be retained.

“Our plans may be the first of their kind, but sharing of services in this way can no longer be viewed as a radical concept. It will soon become the norm for local authorities looking for innovative ways to keep costs down while delivering high quality front line services.”

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