The future of Gunnersbury Park is being decided behind closed doors, furious campaigners have claimed.
Bela Cunha, former chairwoman of the Gunnersbury Park Covenant Group, has accused council leaders of 'abusing' their powers by holding 'secret' unminuted meetings.
For many years, representatives from the park's joint owners, Hounslow and Ealing councils, met every month in public to discuss how to save the rapidly decaying grounds.
However, a new board was established last year in a bid to speed up the park's regeneration and all meetings are now held in private.
Ms Cunha, of Lionel Road North, Brentford, requested minutes of those meetings from Hounslow Council in May and is still waiting for a response more than six weeks later - well beyond the 20-day time limit allowed under the Freedom of Information Act.
She fears residents are being deliberately frozen out of the decision-making process so a deal can be struck with developers - something both councils fiercely deny.
"Holding secret meetings about how to spend public money is a diabolical abuse of council powers," she said.
"This is a huge area of incredibly valuable real estate and I'm worried they're trying to find some way of selling part of it to developers."
English Heritage last week included the historic Brentford park in its first Heritage at Risk register, which lists the country's most endangered sites.
The 186-acre site in Gunnersbury Avenue contains 21 listed buildings, nine of which are deemed 'at risk' by the national charity.
A spokesman for Hounslow and Ealing councils said the new board met in private to 'avoid certain issues that hindered progress in the past'.
"Options for the park will be fully consulted upon," he added.
"In addition, a stakeholder group will offer local people and interested parties an opportunity to influence decisions and make suggestions to the regeneration board."
Anyone interested in being a representative on the park's stakeholder group should call 020 8992 1612.