Boris Johnson has defended his decision to skip a crunch vote on Heathrow expansion after critics accused him of breaking a promise to constituents to oppose the building of a third runway.
The Foreign Secretary, who has flown to Afghanistan, said his "resignation would have achieved absolutely nothing" as he predicted the runway will not be built and vowed to continue to oppose it from within Government.
Mr Johnson has been given carte blanche to miss Monday’s vote when MPs will be asked to back the plans.
He was given permission to be out of the country which means he will not have to decide between supporting the Government and voting against the plans which would likely have required him to resign.
Mr Johnson had previously pledged to “lie down… in front of those bulldozers” to stop expansion when he was elected the MP for Uxbridge and South Ruislip which is just north of the Heathrow site.
Mr Johnson outlined why he is missing the vote in a letter sent to councillors in his constituency.
In the letter, seen by the Evening Standard, he said: “I have made clear my opposition since joining the Government, and I will continue to lobby colleagues from within government.
“Some of my critics have suggested that I should resign over the issue. No doubt they have my best interests at heart.
“But it is clear from what is likely to be a large majority of MPs who are in favour of a third runway that my resignation would have achieved absolutely nothing.”
Mr Johnson said he believed the “very considerable difficulties” facing the development mean it will “be a very long time” before he would have to “make good” on his bulldozer pledge “if indeed a 3rd runway ever comes about”.
But the Foreign Secretary has faced fierce criticism for missing the vote with his own Tory colleagues urging him to “put his money where his mouth is” and oppose the plans.
The Government is expected to win the showdown in the House of Commons with Tory MPs on a three line whip to back expansion and Labour MPs, many of who support the runway, being given a free vote.
But Mr Johnson’s decision to miss it has prompted accusations he had broken his promise to his constituents.
His position was placed under even greater pressure after his Tory colleague Greg Hands quit last week as international trade minister so that he could keep his own pledge to oppose development.
Asked if Theresa May believed Mr Johnson to be an “honourable” man, her official spokesman said: “You are asking me the question ‘is the Foreign Secretary an honourable man’, well the answer would be 'yes'.”
Mr Johnson will not be the only Cabinet minister to miss the vote with Philip Hammond, the Chancellor attending a meeting in India.
He tweeted: “A third runway at Heathrow is a vital part of the infrastructure that will support a prosperous global Britain. I am fully in favour of #HeathrowExpansion and would be voting in support if I wasn’t in Mumbai for the @AIIB_Official Annual Meetings.”
A Downing Street spokesman said: “It is not uncommon for ministers to be slipped when they have business abroad.”
The Prime Minister confirmed last week that Mr Johnson would be missing the vote as she said he would be the “living embodiment of global Britain”.
The Government initially would not say where the Foreign Secretary had gone to, citing security concerns for the lack of clarity.
But it emerged on Monday lunchtime that Mr Johnson had gone to Afghanistan, with the country's Ministry of Foreign Affairs tweeting a picture of him meeting an Afghan counterpart.
Chris Grayling, the Transport Secretary, said he did not know where Mr Johnson was as he took to the airwaves on Monday morning to explain the Government’s support for expansion.
He told BBC Radio 4’s Today programme: “I have no idea where Boris is. Genuinely no idea where Boris is. But the Prime Minister has been very clear that there are people in the party who for various reasons have had long held views about the airport and we are not going to whip those people into voting.”
He added: “What he decided to do on the vote is very much a matter for Boris himself.”
Sarah Wollaston, the Conservative chairwoman for the Health Select Committee, said Mr Johnson should have “put his money where his mouth is” by voting against the plans.
She added that “just being conveniently out of the country I’m afraid won’t wash".
Justine Greening, the Conservative former Cabinet minister and critic of expansion, also took a thinly veiled swipe at Mr Johnson as she said she "wouldn’t want any long term MP campaigners against
#Heathrow expansion to miss their chance to represent their community".