Fears for the green space in front of Hornsey Town Hall might be calmed as Haringey Council promise it will stay open for the public when it falls into private ownership.

But campaigners are concerned a future owner could close the square for private events and that there is a lack of transparency in the bidding process.

Haringey Council is shortlisting bids from four developers to buy the 1930s art deco Hornsey Town Hall, the square, the Town Hall annex and the car park.

The council guarantees the square will be accessible, but campaigners fear it could be lost for future generations.

Eleanor Greenaway, a member of the Crouch End Neighbourhood Forum, launched an online petition, signed by 521 residents, to “rescue Hornsey Town Hall green from developers.”

The petition says: “Hornsey Town Hall green, the only green space in Crouch End, is about to be sold to developers and may be lost as a public space. The council has many unanswered questions.”

Mark Afford, a member of the Hornsey Town Hall Appreciation Society, believes there could always be a catch.

“They could close it off for private functions,” he said. “It’s like the Garden Bridge [the proposed new bridge over the Thames.] They say it’s for everyone and then it turns out it’s privately owned - the assurances are not there.”

Once a developer buys the plot, the appreciation society hope there will be a public consultation about how the space will be used.

There have been ongoing complaints about the current state of the square, including litter-strewn fountains, but the council said the fountains were cleaned on Wednesday for the start of the summer.

Bids are being reviewed by Haringey Council and the community-led Hornsey Town Hall Creative Trust.

A Haringey Council spokesman said: “As we have always made clear, Hornsey Town Hall Square is guaranteed to remain publicly accessible under any future plans, and that commitment will be written into legal agreements.”