The government will also allow local authorities who work together to have their own "conurbation mayor" should they want one.

BBC: Have ministers really embraced Heseltine's revolution?

"The costs in terms of traffic delays as a result of piecemeal maintenance will be badly felt by road users in the south-east Dorset conurbation, " he added.

BBC: Bournemouth Spur Road ?20m government funding refused

The new Toronto will have clout in negotiations with the 4.5m-strong conurbation around it, where the Greater Toronto Services Board rules over strategic plans and major roads.

ECONOMIST: Canada

Take Middlesbrough, a city in the northern Teesside conurbation.

ECONOMIST: Reshaping local government

Approximately half of the city's 13m population (part of a 20m conurbation) lives in the slums areas of unregulated, poor-quality structures, usually built of mud or brick and asbestos sheets, with no sanitation.

ECONOMIST: Light in the darkness

"York Minster has stood at the heart of the city for centuries, but even before that, this site was instrumental in the growth of York, from a military barracks into a major conurbation, " said the Dean of York, the Very Reverend Vivienne Faull.

BBC: Exhibit at York Minster