The politician responsible for bringing economic development to Birmingham last night insisted the city council was not in the pockets of supermarket chains and would not automatically sell land for new stores.

Ken Hardeman, cabinet member for regeneration, defended a council study which welcomed the growth of superstores, said they were popular with shoppers, and suggested they bring significant benefits to the local economy.

The cabinet meeting also considered a separate report, pointing out that almost one-third of Birmingham's suburban shopping centres have been hit by new superstore developments and are in danger of failing.

Coun Hardeman (Con Brandwood) described an investigation into the impact of 14 Birmingham superstores as a factual report which did not "over-endorse supermarkets or decry them".

He added: "This report says to me that superstores are not the threat that some people think they might be. In some parts of Birmingham super-markets have been an essential part of bringing about vibrant economic centres."

He accepted, however, that parts of the study could be interpreted as being over-supportive of the big-four superstore firms - Tesco, Asda, Sainsbury and Morrisons.

"It does give the impression that supermarkets are our best friends, but I am suggesting that is not the case," Coun Hardeman added.

He pointed out that four superstore planning applications have been rejected by the council since 2003.

The study welcomed regeneration benefits offered by the superstore chains, which often amount to multi-million pound payments to the council for environmental, leisure and transport improvements as a condition of receiving planning permission.

The report added: "The overall implications of the probable expansion of large supermarket representation in Birmingham are likely to be positive."

The council is facing a difficult decision over an attempt by Tesco to acquire part of playing fields at Brockhurst Road, Hodge Hill, to build a new superstore. Residents groups want the council to resist selling the land.

Roger Gordon, representing the Hodge Hill Residents Association, said: "If the council wants to prove it is not in the hands of the superstore chains, then all it has to do is decide not to sell playing fields to Tesco. It is as simple as that."

Council lawyers sought to dampen a suggestion in the superstore report that the local authority could face legal action from store owners if it refused to sell sites. The report noted: "It may be possible for the council to decide not to assist supermarket developments by refusing to sell its land or to assist site assembly through the use of CPO powers but such decisions could be, dependent on their circumstances, challenged judicially."

Mirza Ahmad, council chief legal officer, told the cabinet: "I want to reassure members that developers cannot force us to sell land that we own, but if there is a CPO there may be a legitimate exception. If the council decided to retract from the CPO, there could be legal implications."

Mr Ahmad said the council could negotiate with the big four superstore companies about land sales without being in any way committed to going through with a sale.

Sir Albert Bore, leader of the Labour opposition group, said the council had in the past acted like an ostrich with its head in the sand as far as the superstore issue was concerned.

Sir Albert (Lab Ladywood) said: "The development of supermarkets will be with us for years to come. We are all a bit hypocritical because there is probably no one in this room who does not shop in a supermarket.

"This report gets it correct. We need to be working positively with operators in order that we get the best advantage out of any development opportunity. That is not to say we lie down and take whatever is offered to us.

"Over the past few years the negotiations we have had with supermarket chains have been most beneficial in terms of the contribution we have received from them."