Campaigners say they are determined to reduce noise levels from Heathrow Airport regardless of whether a third runway ends up being built.

Last month a consortium of local authorities and environmental campaigners applied for separate judicial reviews into the £14 billion expansion that the Government voted in favour of in June.

John Stewart, chairman of HACAN, a group campaigning against the plans said he is “not resigned” to the fact the expansion will happen but is preparing for the eventuality and committed to reducing noise pollution.

Mr Stewart said: “If there’s not plan B, we’re stuck.

“Whether the expansion happens or not we’re going to continue to campaign for a reduction in noise.”

Data from new action plans drawn up by major airports across the country has revealed that the number of people affected by noise pollution from Heathrow Airport is 725,000 – higher than any other airport in the UK.

That is more than seven times higher than Manchester Airport – whose noise pollution levels came second to that of Heathrow and recorded that it affects 100,000 people.

John Stewart, who collated the figures, said they confirm just how many people are affected by noise from Heathrow.

He said: “It puts a huge onus on Heathrow to find ways to lessen the noise burden whether or not a third runway is built.”

Mr Stewarts wants flights to be stopped between 11pm and 6am to protect residents living in Leystone, Leyton and Wanstead.

He said: “Children can’t go to sleep and a lot of people get woken up.

“It tires people, they get tired during the day and then they can’t function properly.”

Although there have been no official estimates of the number of people noise pollution could affect if a third terminal at Heathrow was built, Mr Stewart has his own ideas.

He said: “If we have to estimate it would be almost certainly over one million.”