All-day flights threat across London

Parts of London face overflying passenger jets throughout the day after ministers backed increasing the use of Heathrow's runways to deal with delays.

Currently, the airport's two runways are used alternately for take-offs and landings, changing at 3pm, to allow residents in different areas a break from aircraft noise. But the Government is supporting mixed-mode operations - take-offs and landings - on both runways to deal with peak demand and delays at the airport operated by BAA.

MPs reacted angrily, with Putney Conservative Justine Greening saying: "This is a disgraceful disregard for residents. They will pay the price for BAA's incompetence and the Government's unwillingness to confront it."

She said runway alternation was introduced to give people in different parts of London some respite from plane noise.

"It was never done on the basis that when BAA could not run its airport effectively that it would just be ditched," she added.

Ministers had signalled their support for mixed-mode use of runways at Heathrow to expand capacity.

But they have now strongly made the case for it to increase "operational resilience" - avoiding chaos hitting thousands of passengers with delays and cancellations.

In reply to a report by the Commons all-party transport committee into BAA they said mixed mode "could provide greater flexibility for the airport to cater for peak demand and to recover from delays caused by, for example, adverse weather conditions."

Campaigners who believe ministers have already decided to allow a third runway at Heathrow are likely to have their suspicions fuelled by their response.

The Department for Transport stressed the public had been consulted over possible changes at Heathrow.

The MPs' report also called for the break-up of BAA, saying its dominance had stifled competition and was "bad for passengers" and the aviation industry.

But the Spanish-owned airport giant, which serves nearly 150 million passengers a year, argued that a break-up would only delay "the provision of extra runway and terminal capacity". The Government said it would be " inappropriate" for it to comment on a possible break-up of BAA while the Competition Commission is carrying out an inquiry into airport services. It comes as Transport Secretary Ruth Kelly faces a High Court challenge tomorrow from a group of South-East town halls that claim her department broke its own rules by allowing noisy planes to continue flying into Heathrow before 6am. Wandsworth, Richmond and Windsor and Maidenhead councils argue that the Boeing 747-400 RR, a widely used plane, was placed in the wrong noise category. Wandsworth council leader Edward Lister said: "We are aiming to achieve some much needed relief for residents in the 4.30-6am period. Those aircraft which break the rules should be grounded."