Temporary planning permission has been granted for a 9ft Tetra radio mast in an area of outstanding natural beauty.

The mast will be in place for five years at Court Barn Farm on Devil's Dyke Road, Brighton, and will replace an unauthorised mast already there.

It was decided to grant permission because the new mast will be smaller and will be screened by a barn.

The current mast is 13.7ft high and was set up by O2 Airwaves in 2003.

It was granted temporary planning permission for a year, which has now expired.

Anti-Tetra campaigners have already registered concern about the current mast, which is part of a network servicing police radios.

There are concerns about the possible health effects from Tetra radio base stations because of the radiation they emit and some people living near masts have complained of health problems.

Brighton and Hove Green Party councillor Richard Mallender said: "Quite apart from the health concerns there are better and more up-to-date systems than this available on the Continent.

"Tetra is already older than the new 3G phones and the Green party believe the police are paying over the odds for old technology."

The new mast, made of timber with three antennae, has been approved by the Sussex Downs Conservation Board.

It will be removed in five years time as the barn screening it is considered to be in a state of dilapidation and may be removed within a few years.

A spokeswoman for Brighton and Hove City Council planning department said: "With all telecommunications applications, the operators are required to submit a certificate stating the equipment will meet international guidelines on non-ionising radiation protection.

"The applicants have submitted this certificate and planning policy guidelines state, where this is the case, it should not be necessary for the local planning authority to further consider the health aspects."