Richmond Park MP and Conservative mayoral frontrunner Zac Goldsmith has confirmed he will trigger a byelection should his party back Heathrow expansion.

Mr Goldsmith, who was re-elected with an increased majority of more than 23,000 in May, also said he would concentrate on his mayoral ambitions rather than stand as an independent and fight two simultaneous campaigns.

Mr Goldsmith is currently the bookies’ favourite for London’s next Mayor after receiving the consent of 79 per cent of his Richmond Park and north Kingston constituents to put himself forward for the role in a ballot carried out in June.

In 2008 he pledged to trigger a byelection for his Richmond Park seat should the Conservatives give the green light to Heathrow expansion and has stood by his statement.

Mr Goldsmith told the Richmond and Twickenham Times: "It was not a one-term promise.

"But I am convinced we have won the arguments in relation to Heathrow expansion, and fully expect Heathrow expansion to be ruled out altogether.

"For my part, I will keep up the pressure in every way I can until that happens."

Speaking on LBC Radio last week, Mr Goldsmith said he would fight expansion any way he can and would be afforded , should he become Mayor of London next May, he will be provided with another opportunity to do that.

He said although he has been described as the frontrunner for the position there are a few people that have a solid claim to become the Conservative candidate.

He said: "It is a very complicated selection process and will be a hell of a battle to spend the next few weeks persuading members of the Conservative Party across the whole of London that I am the person who is most likely to win and that if I do win it I will be the best for London."