Over 270 of Britain’s business leaders signed an open letter to the prime minster demanding the government implement the Airports Commission’s clear and unanimous recommendation to expand Heathrow.

The letter – sent from signatories ranging from FTSE chiefs and Britain’s key business and trade associations, to leading global brands and SMEs spanning the whole of the UK – sends a clear message that UK business growth and productivity is being held back by lack of capacity at Heathrow.

As the UK’s biggest port and only hub airport, businesses rely on Heathrow’s global network to reach fast-growing emerging markets – more capacity will improve connectivity both within and outside the UK, driving exports and stimulating growth across the country.

Further delay will be increasingly costly and will be seen, nationally and internationally, as a sign that the UK is unwilling or unable to take the steps needed to maintain its position as a well-connected open trading economy in the twenty first century.

Prime minister David Cameron set up the commission in 2012 to find the best way to maintain the UK’s status as an aviation hub.

The business leaders signing the letter join SMEs from up and down the UK, politicians from across the political divide, major trade unions and a majority of people in Heathrow’s local communities in backing Heathrow’s expansion plans.

Heathrow chief executive John Holland Kaye said: “The prime minister showed leadership in establishing an independent Airports Commission.

“It unanimously concluded that expanding Heathrow is the best way of securing Britain’s future as a powerhouse in the global economy.

“Now the Prime Minister has the opportunity to show he is serious about delivering Britain’s long-term economic plan by listening to businesses from across the UK and backing Heathrow expansion.

“This debate has never been about a runway – it is about the future of our country. Let’s get on with it.”