A multi-million pound move by Norfolk County Council to buy the former air base at RAF Coltishall has been criticised by opposition councillors, who say the authority needs to make its business plan public.

The ruling Conservative cabinet last week agreed in principle to purchase RAF Coltishall after the Ministry of Justice picked the county council as its preferred bidder for the 600 acre-site.

The authority, which has not revealed how much it plans to pay for the base, has indicated it would like the majority of the land to be used for agriculture, with its own tenant farmers leasing land.

It added that former air force buildings could be converted into about 65 homes, while other buildings, such as refurbished hangars, could be offered to small or medium-sized businesses to buy or rent.

But with no masterplan drawn up yet, the opposition Liberal Democrat group at County Hall say there are too many question marks hanging over such a major investment of public funds.

They have 'called in' the decision to be looked at by the council's cabinet scrutiny committee and want the Conservatives to show exactly what they intend to do at Coltishall.

Mike Brindle, Liberal Democrat group leader said: 'It baffles me that the council can proceed with what is a substantial investment with no business plan.

'While we are fully supportive of the concept of redeveloping the former RAF Coltishall site, we know there are private bidders who have consulted with local residents as to their plans for the site, we do not think it is too much of the council to do the same and declare their plans for the site before they proceed with spending a large amount of Norfolk tax-payers' money.

'I hope the administration will come to the scrutiny committee with a detailed business plan so that councillors and the public can judge their motives for the site and decide whether or not to support the project.'

The Lib Dems have requested that Cliff Jordan, cabinet member for efficiency, Mike Jackson, director of environment, transport and development at County Hall and Mike Britch, managing director of Norfolk Property Services attend the meeting.

They also want Bruce Giddy, managing director of the Hans House Group of Companies, which had plans to create a heritage centre and museum at the base, to attend.

Mr Jordan said it was too soon for a detailed business plan to have been drawn up and said there was no secret about the council's proposals for the base.

He said: 'I've been delighted that the public reaction to the news that we are seeking to bring the former Coltishall site back to life for the benefit of Norfolk's economy and the local community has been greeted so positively by a large number of people, including local parish councils, the business community and local MPs such as Norman Lamb.

'We are, of course, some way from concluding a deal with the Ministry of Justice, but I am convinced the price we are prepared to pay will offer very good value for money for local council taxpayers and that it is in the long term interests of our county.

'All we have done so far is set out a high level outline for possible uses for the site and as we have said, we want to hear people's views on those and any others through the proposed new liaison group.

'Given that we do not own the site, and will not do so for some time yet, it would have been premature to produce a detailed business case for the entire site prior to any discussions with interested parties taking place. We have made no secret of our intentions.

'Having said that, I welcome the opportunity for a further discussion at cabinet scrutiny because I am convinced that we are doing the right thing for Norfolk and the case stands firmly on its own merit.

'Failing to intervene in this matter would have been a failure for the people of our county and I firmly believe that bringing the site into local public ownership offers the best way forward for a site which has been left alone for far too long.'

The council's cabinet scrutiny committee will meet to discuss the call-in at County Hall next Tuesday.