which they say "would be a reckless gamble" if the economic benefits could not be guaranteed. They also say that Heathrow cannot physically accomodate four runways, which is what would be required for an airport capable of sustaining competition with Paris and Frankfurt. The councils say that ruling Heathrow out of the debate now would bring the Davies Review reporting date -- currently set at 2015 -- forward by at least two years and end uncertainly hampering the industry. Cllr Ravi Govindia, Leader of Wandsworth Council, said: "Even if two new runways were added to Heathrow we cannot be sure of getting new routes to emerging markets. Since Terminal 5 opened the number of destinations served has actually decreased. Expanding this airport further is too reckless a gamble when the environmental price is so high. "The Davies Commission should focus its attention on viable locations and accelerate the decision making process." Cllr Jagdish Sharma, Leader of Hounslow Council, said: "Heathrow is a vital part of our local economy but it needs to be better, not bigger." Business commentators say Heathrow is responsible for around 200,000 jobs in West London, one in five, and the commercial property values around the airport are generally significantly raised due to the location. Heathrow's closure, something required by a number of the funding models for a new airport elsewhere, would present a significant economic challenge to the sub-region. Heathrow featured strongly at Place West London, where speakers from both sides of the debate argued their