If they win, a green paper suggesting ways to reform local government in order to bring in city mayors or even city regions could appear as early as October.

The idea of a green paper is being promoted by Treasury officials mindful that recommendations for changes to local government finance in the light on the on-going Lyons review may be imposed on a local government structure that is out-of-date.

Part of the debate centres around the role of regional development agencies (RDAs) like SEEDA, which some people in government think should be kept without any boundary changes while others don't like RDAs and think city regions should be set-up in their own right.

Commentators suggest the ODPM could be split into two separate departments – one for housing and another for local government. Alternatively it might be retained, but with a new minister in charge. Rumours circulating in Whitehall suggest the ODPM could take on some of the Home Office's local functions and become a Department of Communities - perhaps headed by former home secretary David Blunkett.