Expanding Britain's biggest airport is just one of a number of options that have been put forward by the Department for Transport (DfT).

Others include a new four-runway airport at Cliffe near the River Thames in north Kent, and up to three new runways at Stansted airport in Essex.

There could also be a new airport serving low-cost carriers and freight operations at Alconbury near Huntingdon in Cambridgeshire.

The government proposals are designed to cope with the expected surge in demand for air travel over the next 30 years.

Homes demolished

However, protest groups have already formed, with reports that 10,000 homes around Heathrow will have to be demolished because of a massive increase in air pollution.

The public will be able to view the proposals on 20 and 21 September as part of a four-month consultation period, which ends in November, on the whole issue.

A DfT spokesman said people would be able to speak to officials and discuss how a third runway, if it is ever built, would affect them.

Similar presentations outlining the proposals for Cliffe and Stansted have already taken place.

The exhibition for Heathrow is being held at the Renaissance Hotel, Bath Road, in Hounslow in west London.