The issues: economy versus environment

●A third runway would add an extra 220,000 flights by 2030 and the Government estimates this would bring the British economy an additional £9 billion. Pro-aviation groups say that without expansion, limited capacity would increase the cost of flights for ordinary families.

●Campaigners say Heathrow will effectively be "full" soon and warn that projections show that the number of international visitors to the UK is set to rise from 32 million to 82 million by 2030. Although the recession will hit trade in the short term, governments should look to the longer term when growth will pick up again.

●In a globalised world, businessmen need to travel more. A third runway would fend off competition from Amsterdam Schiphol for passengers wanting a hub airport for transfers to other destinations. It is also claimed that without new runways, the UK would lose half a million new jobs in the tourism industry that would be generated from meeting demand from overseas visitors.

●Those arguing for a high-speed train link to the North are offering a false choice. Only three per cent of Heathrow flights go to Manchester or Leeds/Bradford.

●New planes are quieter and cleaner. BAA says it will reduce the number of flights at an expanded Heathrow if airlines fail to adopt the new fleets.

●Air freighting some products, such as flowers from Kenya, helps poorer countries while having less impact on the planet. Growing flowers in Kenya in season uses less energy than growing them under heat lamps in Europe in winter.

●Pollution from car travel to Heathrow could be countered by better public transport.

●The greenhouse gases produced by flying are far outweighed by those produced by industry, heating homes and car travel.