BORIS JOHNSON should pay back the cost of a visit to Afghanistan that meant he avoided a crunch vote on a third Heathrow runway, Labour said on Wednesday.

Foreign Office officials refused to reveal the flight and security costs for Mr Johnson’s trip but said the bill for three members of staff who accompanied him totalled £19,366, independent investigative website The Ferret reported.

The former foreign secretary was mocked by MPs for missing the vote for his nine-hour diplomatic visit to Afghanistan.

He had pledged to his Uxbridge and South Ruislip constituents that he would lie in front of bulldozers to stop the expansion.

He would have been forced to quit the government if he had gone against the plans.

Shadow chancellor John McDonnell, whose Hayes and Harlington constituents live next to Heathrow Airport, criticised Mr Johnson for “scuttling out of the country” at taxpayers’ expense, saying he should use his columnist earnings to cover the bill.

“Perhaps our former foreign secretary will consider using some of the money he earns insulting Muslim women with his lucrative £20,000-plus a month column to pay back the taxpayer,” he suggested.