Residents and conservationsits are against plans for the airport

Unless the problem was carefully managed, an airport "could not operate" on the Hoo Peninsula, in Kent, the government commissioned report said.

Transport minister Alistair Darling told MPs the hazard posed by the birds was severe and would probably be higher than at any other major UK airport.

A plan for an airport at Cliffe with up to four runways was put forward as an option in July 2002.

On Monday, Mr Darling published a Cliffe birdstrike report commissioned by the Central Science Laboratory and the British Trust for Ornithology.

Among the report's conclusions was that without a comprehensive and aggressive bird management programme incorporating careful and considered airport design, appropriate habitat management and active bird control, an airport could not operate safely at Cliffe.

Plans for an airport at Cliffe have been met with fierce opposition from local residents and conservationists.

Mr Darling said he would consider the report carefully before making his decision about Cliffe and other airport expansion in an aviation white paper later this year.