Dredging companies have published an environmental assessment to support plans to dredge sand and gravel off the Sussex coast.

Six operators are seeking new licences to work 20 miles off Beachy Head, near Eastbourne, claiming new areas are needed because aggregate reserves are dwindling.

The sites are far further offshore than areas where dredging is permitted.

The East Channel Association, formed by the firms, said quarrying would have to increase by 70 per cent if new marine sites were ruled out.

Spokesman Dr Andrew Bellamy said the assessment had tested the cumulative effects of dredging.

He said: "These would be minor given our pledge to minimise the area dredged and to monitor the effects of dredging."

The companies plan to dredge 8.5 million tonnes a year for 15 years.

Full recovery of fish populations is expected to take four to six years.

The companies involved are: Britannia Aggregates Ltd, Dredging International (UK) Ltd, Hanson Aggregates Marine Ltd, RMC Marine Ltd, United Marine Dredging Ltd and Volker Dredging Ltd.

Deputy Prime Minister John Prescott's office will decide about the licences.