A stunned British aviation industry has rounded on the Conservative party after David Cameron pledged to scrap a third runway at Heathrow in favour of a north-south high-speed rail link.

British Airways (BA), the most vocal backer of expanding the UK’s biggest airport, accused the Tories of endangering the national economy and ignoring the calls of the business community for a new runway.

BA said: “It is disappointing if the Conservatives are now saying they would turn their back on jobs and wealth creation, and put the UK’s air links in a straitjacket not imposed anywhere else in the world.”

The airline added that the proposed route of the 180mph rail link, from London to Birmingham, Manchester and Leeds, would generate minimal competition to Heathrow because it will travel through cities that account for only 3% of the flights to and from the airport. BA said: “In any event, many transfer passengers may still prefer to fly to Heathrow than take a rail alternative. We urge the Conservatives to think again.”

BAA, Heathrow’s owner, was more measured in its response but repeated BA’s argument that a high-speed rail would not solve the overcrowding problem at Heathrow.

A spokesman said: “BAA believes this country needs both a third runway at Heathrow and high-speed rail. To prioritise one over the other is a false choice and will put Britain’s future competitiveness at risk.” The Board of Airline Representatives, a trade body for 90 airlines, said scrapping a third runway would “seriously impact” upon the UK economy.