Plans to allow community groups to manage south London’s biggest summer festival could kill off the show, it is feared.

Opposition councillors claimed the Lambeth Country Show, which cost £470,000 to stage last year and attracted about 180,000 people to Brockwell Park, will “wither on the vine” if the council hands it over to residents in the future.

Lambeth Council insisted the event could be successful if groups such as the Herne Hill Forum or Friends of Brockwell Park took control of the event as part of its ‘co-operative’ approach.

It is understood organisers would be responsible for booking music acts, arranging stalls, managing budgets and security, as well as ensuring the show generated almost £200,000.

Council leader Steve Reed said the move would “empower communities”.

He said: “It is not about cutting costs. It is about giving them the power.

“If groups such as the Herne Hill Forum want to run it, then they could run it in the way they want to.

“Generally people are keen to have control of what happens in their local parks.”

But opposition councillors believed the changes could threaten the show’s viability.

Councillor John Whelan, Conservative group leader, said: “I think it is aspirational thinking, but in order to be able to generate commercial sponsorship and meet the expectations of the public, the Country Show needs a professional management company, otherwise it will wither on the vine.

"The voluntary organisations Coun Reed is talking about simply lack the capacity to handle this type of organisation.”

Councillor Ashley Lumsden, Liberal Democrat group leader, said he supported the proposal if it ensured the show’s future, but was concerned about the budget provisions.

He said: “Given the luke-warm interest the council has shown towards the Country Show, it may well be a good thing to get it out of the hands of the council and get it into the community.

"But we'll have to watch the budgets as other services transferred to the community like libraries have seen cuts in their cash of up to 60 per cent."

Peter Bradley, chairman of the Friends of Brockwell Park a group that could be invited to organise the show, expressed its fears about the proposals.

He said: “It would be nice if [Coun Reed] talked to us first.

“We are not an event organising company.

“In the past the council had contracted the show out to an event organiser.

“Then they took it ‘in house’ again, perhaps because they thought they would make more money.

“But the event needs a big event organiser.

“The idea of the big society is fine, but if it is an excuse for the council to get rid of the responsibility, rather than a good way of working, then it is a con.”

Giles Gibson, chairman of the Herne Hill Forum, said he supported the idea in principle, but said “we cannot do it alone”.

Last month, the council announced September dates for this year’s Country Show after a public backlash against the decision to cancel it.

Officers and councillors cited security fears during the Olympic year as the main reason for a postponement because of overstretched police resources.

It is estimated this year’s replacement show will cost the council £275,000 – about half what it would cost to stage it in July.