Countryside campaigners have only a month to object to parts of the Downs losing conservation safeguards.

Draft orders to end area of outstanding natural beauty (AONB) protection for land not in the proposed South Downs national park are due to be published on August 27.

A total of 53 pockets of land on the fringes of the Downs will be affected.

The largest and most controversial areas set to lose AONB protection are around Brighton and Hove.

They include the cliff top between Saltdean and Peacehaven, Toad's Hole Valley in Hove, the University of Sussex campus in Falmer and the site in Village Way North, Falmer, being proposed for Brighton and Hove Albion's new stadium.

Chris Todd, of the pro-national park South Downs campaign, said: "We are very concerned about some of these areas, which are obviously of outstanding natural beauty and well connected to the Downs but face losing protection.

"The whole point of a national park is to increase the protection."

The Sussex Downs AONB was created in 1966. It would be the first time any AONB land in England and Wales was lost without alternative arrangements being put in place.

The Countryside Agency, responsible for the changes, said areas set to lose protection were those affected by development or where the boundaries were unclear or the land had been degraded.

The agency stressed protection would continue until the park was operating, not expected to be before 2006.

The draft revocation orders will be available for inspection at main council offices and objectors have until September 27 to comment.

There could be changes before the orders are confirmed in November.