London Mayor Boris Johnson would breach his strategic role by taking over the delivery powers of the Homes and Communities Agency’s London arm, councils have been warned.

A report to think-tank London Councils by its policy and public affairs director Dick Sorabji says councils should oppose Johnson’s attempt to take on more development powers from Whitehall and quangos.

The report, which supports most of Johnson’s plans for devolution, urges council leaders to oppose the mayor’s encroachments on their roles ahead of the Decentralisation and Localism Bill expected in the autumn.

Johnson has proposed that the Homes and Communities Agency in London should become an executive arm of the Greater London Authority.

“The mayor’s role is a strategic and not a delivery function. The idea of such a power …fundamentally breaches this principle,” the report says.

“It would also cut out borough representation on HCA London Board. The new London housing and regeneration organisation should be a free standing entity.”

The report also objects to the mayor’s plan to take charge of a successor development corporation to the Olympic Park Legacy Company. It says this should instead go to a board with majority borough representation.

In the report, London Councils are urged to influence the Decentralisation and Localism Bill.

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