Within minutes of permission for the third runway being announced, an MP protesting against the decision was suspended from Parliament while those opposing the scheme have already spoken out against it.


In announcing the plan, transport secretary Geoff Hoon said the decision was largely made due to economic factors although he admitted green issues surrounded the £9 billion expansion.


The building of high-speed rail networks to the north and Scotland as well as the airport, which Hoon also announced was supposed to quieten green critics.


However, protests have already begun, most notably by Hayes and Harlington Labour MP John McDonnell whose constituency borders the now-doomed village of Sipson where around 2,000 people will lose their homes to make way for the runway.


McDonnell struck as Hoon announced MPs would not be able to vote on the decision. Marching down from the backbenches, McDonnell picked up the mace from the dispatch box and placed it on an MP’s seat.


Touching the mace is seen as a sign of protest by MPs and after refusing to end his protest, McDonnell was ordered out of the Commons and suspended for a week.


He is just one of more than 50 backbench Labour MPs who have openly opposed the scheme while several cabinet ministers are also unconvinced about its validity.


Reports had been circulating earlier this week that the announcement may even be postponed while prime minister Gordon Brown sought to quell the rebellion although he has obviously decided to press on with it, saying environmental conditions would be taken into account.


However, shadow transport secretary Theresa Villiers told BBC Radio 4’s Today any government environmental promises would now be shown “to not be worth the paper they are written on” and again pledged to cancel the project should the Tories win the next election.


In the Commons she added: “This is a bleak day for our environment and for all those of us who care about safeguarding it.”


The Liberal Democrats also oppose the third runway and have urged ministers to invest in high-speed rail links instead.


Lib Dem spokeswoman Susan Kramer added: “There’s this conventional wisdom amongst business that you must grow the airport … it just isn’t held up by the reality. Actually Heathrow has been serving fewer destinations over the last ten years.”


While permission may have been granted for the runway’s go-ahead, it must still go through the planning process which is expected to be a lengthy one given the opposition and legal challenges expected.


Environmental campaigners claim the new runway would kick into touch the government’s legal commitment to cut carbon emissions by 80% by 2050.


Earlier this week Greenpeace backed by a number of celebrities announced it had bought a parcel of land the size of a football field in the proposed site and its new owners will bitterly fight any compulsory purchase orders.