The Conservatives would give London mayor Boris Johnson more control over property and development in the capital if David Cameron’s party wins the general election on Thursday.

The Tories have also today confirmed plans to introduce mayors to 12 major UK cities, while giving Johnson responsibility for the £1.1bn budget of the London Homes and Communities Agency.

A spokesperson said: “We think Boris has worked well in London, and we think it would be beneficial to have the same kind of structure elsewhere.”

The pledge builds on an idea suggested by the Conservatives last year to strengthen the role of city mayors.

Under the new plans for London published on Friday, Johnson would have new powers over four key areas of housing and regeneration: the Port of London Authority, rail franchises, and the Olympics legacy.

The New Settlement for London’s Government includes plans to create a Mayoral Development Corporation, which would oversee the work of the Olympic Park Legacy Company. This would be accountable to the elected mayor, with planning powers and control over all the relevant public land.

Shadow London minister Justine Greening said: “An important part of our Big Society agenda is to give more power to locally-elected representatives of the people.

“So we have been discussing very carefully with the Mayor’s office what additional powers could usefully be transferred from central government to the Mayor. This paper is the product of these discussions and will be implemented by a Conservative government.”

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