The Government flew in the face of strong opposition today by backing a third runway at Heathrow airport.
The announcement by Transport Secretary Geoff Hoon of a go-ahead for the £9 billion expansion at Heathrow came after Prime Minister Gordon Brown said the needs of the economy and the environment had to be balanced.
Mr Hoon's decision means that the way is now open for a 7,200ft runway - likely to be completed around 2019/20 - to be constructed north of, and parallel to, Heathrow's existing two runways.
The new runway will lead to the destruction of the village of Sipson, with a dual carriageway road likely to go through the area's Cherry Tree cemetery.
Speaking in Germany before the announcement today, Mr Brown said: "It is always our desire to make sure that we protect the economic future of the country while at the same time meeting the very tough environmental conditions that we have set ourselves for noise and pollution and for climate change."
The Government has faced fierce opposition, not only from local residents, environmental groups and local councils but also from Labour backbenchers.
Conservatives and Liberal Democrats are also against expansion, preferring improved rail links to Heathrow instead.
In an attempt to mollify opponents of expansion, Mr Hoon announced plans today for improved rail links from Heathrow. He also said that planes using the new runway would have to meet strict noise and air pollution targets.
The Government and the pro-expansion lobby, which includes airlines, big business and some unions, believe expansion of the UK's biggest airport is essential for the economy of London and the UK.
Building a new runway is likely to lead to the creation of 65,000 jobs.
In a 15-minute statement, Mr Hoon announced a package of transport and environment improvements, including the possibility of a north-south high-speed rail line, to accompany his decision to back Heathrow expansion.
He also said that only the cleanest planes would be allowed to use the new runway and that, initially, the number of extra flights would be limited to 125,000 a year, rather than the 220,000 envisaged in the Government's 2003 aviation White Paper.
This would take the number of flights up to around 605,000 a year from the current 480,000.
In a move that is likely to disappoint airlines and Heathrow operator BAA, Mr Hoon ruled out allowing the so-called mixed-mode approach on Heathrow's two existing runways.
This would have scrapped the alternation process now used, in which local residents get some respite from the noise of planes for half the day.
Mr Hoon said: "Transport is the lifeblood of Britain's economy. In spite of record levels of investment over the last decade, increasing demand means that in many places our transport infrastructure is operating at, or very near, capacity.
"It is essential we take the right decisions now - for the economy, to drive down greenhouse gas emissions by 2050, and to support British jobs.
"Heathrow is vital to our economy. It connects us to the growth markets of the future - essential for every great trading nation.
"But for too long it has operated at full capacity, losing ground to international hub airports in other countries and with relatively minor problems causing severe delays to passengers.
"This third runway will help secure jobs now and in the future and ensure that Britain remains a place where the world can come to do business."
Mr Hoon announced:
* £6 billion to increase capacity on some of the nation's busiest roads - providing an extra 520 lane miles of road by widening and opening up the hard shoulder - as well as new plans to roll out hard shoulder-running across the core motorway network;
* The creation of a new company - High Speed 2 - to help consider the case for new high-speed rail services between London and Scotland. It will be given the task initially of developing a proposal for an entirely new line between London and the West Midlands which could link to Heathrow and Crossrail through a new international interchange station;
* Further work to consider the case for electrifying two of Britain busiest railway lines - Great Western and Midland Mainline - with decisions to be announced later in the year.
* Plans to bring international pressure for international aviation to be part of global deal on climate change, building on aviation's inclusion in the European Emissions Trading Scheme;
* New work to promote international agreement on progressively stricter limits on carbon dioxide emissions from aircraft, similar to those already in place for new cars within the EU;
* The intention to set a new target of reducing UK aviation emissions below 2005 levels by 2050;
* Allowing capacity increases beyond 125,000 flights a year to be approved by the Government only after a review in 2020 by the Climate Change Committee;
* Allowing new capacity to be released only once strict air quality and noise conditions are shown to be met and on the basis of independent assessment;
* The intention to bring in incentives for new capacity to be given to cleaner, quieter aircraft;
*£250 million to get more ultra low-carbon vehicles on Britain's roads, helping motorists to go green by stimulating consumer uptake and helping to reduce emissions from road transport and improve local air quality.
Mr Hoon said that with the mixed mode approach ruled out, he would expect BAA to bring forward a planning application for the third runway so that it could be built as soon as possible in the period 2015-20 so as to reduce delays for existing passengers and improve resilience.
He told MPs: "Having considered all the evidence, I have decided that all three of the Government's conditions for supporting a third runway at Heathrow can be met.
"I can therefore confirm that an additional terminal and the slightly longer runway proposed in the consultation are the best way to maximise the efficiency of a larger airport. "
Mr Hoon went on: "These announcements on transport infrastructure, on motorways, railways, on Heathrow, and on carbon reductions from domestic transport show the Government taking the right decisions for the long term; delivering real help with job creation today, and creating real hope for Britain's long term growth prospects."
He said the Government was providing "real help in securing carbon reductions, real help for rail passengers and real help in increasing the long-term competitiveness of the UK economy by creating excellent transport links to the global economy, ensuring this remains an attractive country in which to do business".
Mr Hoon went on: "Things have improved greatly for those living near the airport over the past 30 years. Improved aircraft technology means that, while in 1974 some two million people around Heathrow were affected by average levels of noise at or above 57 decibels (seen as the irritation level), by 2002 that number had dropped to 258,000 people.
"People who live around the airport clearly value runway alternation and that is why I have rejected more intensive use of the existing runways through mixed mode.
"But we need to do more. The additional measures I am putting in place - on (take-off and landing) slot priority for cleaner, quieter aircraft and the release of new capacity only once environmental conditions are shown to be met - also demonstrate my determination to mitigate the effects of the airport on those who live nearby."
He said the hard-shoulder running could involve the most congested parts of the M1, M25, M6, M62, M3 and M4 and the motorway around Manchester, Birmingham and Bristol.
The new High Speed 2 company will be asked initially to develop a proposal for an entirely new rail line between London and the West Midlands, which would enable faster journeys to other destinations in the north of England and Scotland using both existing lines and a new high speed rail network.
Mr Hoon said: "I see a strong case for this new line approaching London via a Heathrow International hub station on the Great Western line, to provide a direct four-way interchange between the airport, the new north-south line, existing Great Western rail services and Crossrail into the centre of London.
"My intention is that, by the end of this year the company will have advised us on the most promising route or routes, with their individual costs and benefits."
Shadow transport secretary Theresa Villiers said: "This is a bleak day for our environment and for those of us that care about safeguarding it.
"A third runway at Heathrow would inflict devastating damage to the environment and to the quality of life of millions of people and the Conservatives we will fight them every step of the way. We need to make Heathrow better not bigger.
"If Gordon Brown won't do that it's time for them to call a general election so this country can elect a Conservative Government that will stop this environmental disaster from going ahead."
Colin Matthews, chief executive of BAA, said: "This decision opens the door to Heathrow becoming a truly world-class hub airport, and to the UK maintaining the direct connections to the rest of the world on which our prosperity depends.
"Meeting the environmental targets will be demanding, but, while we have to study the detail in today's announcement, we are determined to work with the rest of the aviation industry to achieve them.
"We are also fully aware that today's decision will be a difficult one for many, particularly those residents who will be directly affected by it. We intend to work with the local community as much as possible as we go through the planning process."
British Airways chief executive Willie Walsh said: "This is the right decision for jobs and investment in the UK. Heathrow is our national hub airport and Britain cannot succeed in a global economy without the capacity for excellent air links already built by our international competitors.
"The Government has imposed additional, tough environmental safeguards on the way the airport will operate and a new system for rigorous enforcement. Heathrow will set new world standards for airport environmental performance.
"We are disappointed at the rejection of mixed-mode, which would have reduced Heathrow's vulnerability to delays, but very much welcome the proposal of a high-speed rail hub at Heathrow."
He added that the Government had reached "a balanced decision in the long-term interests of the whole country and I hope people will respect it".