PLANS to expand UK airport capacity are "based on a wing and a prayer" according to two reports from environmental groups.

The organisations ­challenge the claims of the Whitehall-appointed Airports Commission that it is possible to build a new runway and still meet the UK Government's climate change targets. They also argue building a new runway in the south-east of England would worsen the north/south divide, as growth at regional airports would need to be constrained.

The two reports have been released by the Royal Society for the Protection of Birds, nature charity the WWF and the Aviation Environment Federation.

Jean Leston of WWF UK said: "Thinking that you can build a new runway at Heathrow or Gatwick while still keeping to UK climate targets is being ­over-­optimistic and using assumptions that are based on a wing and a prayer, not on the real world."