Oxford Castle developer Trevor Osborne has criticised the city and county councils for delaying his £40m dream.

Mr Osborne believes his vision, formed seven years ago, could have happened much quicker if Oxfordshire County Council, Oxford City Council and other bodies such as English Heritage and the South East England Development Agency had trusted his vision for the development.

And he claims the city centre site, which has seen the former prison and its grounds transformed into 40 apartments, a luxury Malmaison hotel and a range of restaurants and bars, would have taken shape much earlier in the hands of a unitary authority.

He said: "The county council is the landowner and the other has responsibilities for planning.

"So the scheme had unanimous approval from the county council but took about five meetings to be approved by planners.

"Layer upon layer of regulation makes the process slower and it would have been much better with a unitary authority -- it makes sense."

Now Mr Osborne is to set up an Academy of Urbanism on the Castle site -- the first of its kind in the UK -- to improve the relationship between planners and developers.

He said: "One of the problems we have in the business is the gulf of understanding between planners and developers who put up the money and take the risk.

"There is a considerable element of trust when you are working with the public sector, which has been hard to achieve. It would have been much quicker if the trust had been there from day one.

"The result is not very far from the creation in my mind that I formed in the first three months of working there."

Mr Osborne's comments came as a "surprise" to city council chief planner Michael Crofton-Briggs.

He said: "We've worked hard with Trevor Osborne to help him realise his ambition for the site. However, we have had to bear in mind, as have English Heritage, that this is an ancient monument and listed building and a unique part of Oxford's heritage.

"We're surprised by his comments as council officers spent a considerable amount of time working constructively with him at every stage of the project."

Neil Monaghan, head of property at Oxfordshire County Council, which owns the Castle site, said: "We're delighted with what the Trevor Osborne Group has achieved since we saw the potential of the site and invited them in.

"We've worked hand-in-hand with him for many years, sharing in many of his frustrations with the planning process and many other obstacles."

The commercial outlets on the site are now fully occupied with the final leases going to Pizza Express and American doughnut specialist Krispy Kreme.

About 400 jobs have been created, including 80 at the Malmaison Hotel which is due to open on November 28.

The site is expected to generate £20m a year for the local economy.