The Government is considering new alternatives to the controversial expansion of Gatwick airport.

The Department for Transport is seeking information about sites previously considered "long shots" and excluded from a lengthy public consultation.

The news is a boost to campaigners fighting plans for up to two new runways at Gatwick.

Transport Secretary Alistair Darling has still not made up his mind how to boost air capacity in the South East - despite the consultation ending two months ago.

Residents living close to the airport will hope one of the alternatives will force Gatwick out of the running.

One is the expansion of Redhill aerodrome in Surrey, which could be turned into a satellite terminal for Gatwick.

Also under consideration are a site on the Hoo peninsula in the Thames estuary, known as Thames Reach airport, a plan for an airport on the Isle of Sheppey and a new terminal on an artificial island in the Severn estuary.

The Government has asked those backing the four projects for analysis of the cost of road and rail links, passenger numbers and the cost of infrastructure by September.

A spokesman said: "He said: "We're helping them to develop their proposals so we can compare them on a consistent basis with the options we've put forward."

Mr Darling will then rule on where the extra aviation capacity should be provided.

He has promised his decision by the end of the year.

Previously, the alternatives to Gatwick were up to three new runways at Stansted, a controversial new £9 billion airport at Cliffe in Kent, or a new runway at Heathrow.

The Government announced three possible options for extending Gatwick earlier this year.

It had been excluded from its original plans as there had been an agreement in 1979 between airport operator BAA and the local council that there should be no expansion at the airport before 2019.

But this decision was overturned by the High Court judge, forcing ministers to publish a new consultation document.

These included a new full-length runway to the south and parallel to the existing one; a full-length runway about 1,000m to the south of the existing one; or two new runways - one to the south and one to the north.

This option would destroy 430 homes, 18 Grade II listed buildings and take up 530 hectares of green belt.