Burnham dodges questions on Heathrow third runway as project faces four-year delay

A paper published by the Department for Transport this summer showed that airports elsewhere in England and Wales are likely to lose millions of passengers if Heathrow builds a third runway. Photograph: Peter Macdiarmid/Getty Images

Plans for a third runway at Heathrow are once again up in the air after the prime minister refused to say whether he backs the “contested” project which is delayed by up to four years.

Over the weekend it emerged that ​Heathrow no longer expects to meet the original 2035 deadline. Instead, the airport hopes to secure planning permission by 2029 and then open the runway “within a decade”, meaning it would not be operational until 2039.