The Open Spaces Society (OSS) has criticised Ealing Council for its plan to de-register part of Haven Green common to avoid a "legal challenge".
According to the pressure group for common land, the council constructed a small section of a bicycle parking hub on a paved island in Haven Green, opposite Shanakee pub, in 2012 without full government permission.
The council said it has applied to de-register the island, a patch of common land, to avoid the risk of "legal challenge" which OSS claims is an attempt to legitimise the hub.
Areas registered as common land are protected from development, but the council has promised not to sell the land once the change is made, and insists it will not be in danger of falling into the hands of developers.
OSS, whose claims are shared by community group Friends of Haven Green, also believes the council should have offered land in exchange for de-registering the island.
'We deplore this action'
OSS general secretary, Kate Ashbrook, said: "We deplore this action by Ealing Council to remove part of this ancient and much-loved common from the register, when it should be protecting it and enabling everyone to enjoy it.
"While the society supports the provision for cycling, it contends that such provision should not be sited on common land.
"We consider that the council has made little effort to find alternative arrangements for the cycle hub."
According to OSS, the council claims the hub covers 188 square metres - below the 200 square metre threshold whereby the council must offer a replacement.
But Department for Environment, Food & Rural Affairs (Defra) policy still expects land to be offered in exchange for the land being de-registered.
Its Common Land Consents Policy Guidance says: "Even if the land to be de-registered is not more than 200m² the Secretary of State will usually expect land to be offered in exchange for the land being de-registered as her policy is not to allow our stock of common land and greens to diminish."
OSS also described the hub as an "eyesore" that restricts public access.
A spokesperson for Ealing Council said the plan was necessary in order to remove the risk of the hub being removed through a legal challenge.
'Formalise an existing activity'
The spokesperson said: "We have applied for de-registration of a small isolated island of Haven Green which is used for cycle parking and has had this use for decades.
"The council has no intention other than to formalise an existing and recognised activity here and avoid the risk of this popular and extremely well used feature being removed through a legal challenge.
"There is no question of developers being able to encroach on Haven Green.
"The land is owned by the council and we would never consider selling it.
"Haven Green also enjoys protection through national planning policies above and beyond that afforded by village green status."
Asked to comment on the claim that the cycle hub was built illegally, Ealing Council offered no comment because the issue is subject to a High Court challenge from Friends of Haven Green.