Last-ditch deal that bought off Cabinet dissenters

"There have been times when I wish that she had taken the decision," Geoff Hoon, the Transport Secretary, said of his predecessor, Ruth Kelly, after standing up to announce the Government's support for a third runway and sixth terminal at Heathrow. He was only half-joking.

Mr Hoon had just faced almost universal anger in the Commons for going ahead with the £9bn expansion, culminating in John McDonnell, a member of his own party, being thrown out for picking up the ornamental mace in defiance.

And he faces the certainty of having his tenure in office dominated by legal action, public inquiries and accusations that he has shattered the Government's credibility on the environment.

While campaigners, green groups and concerned MPs had been waiting years for the Government's decision, the package Mr Hoon announced to the Commons, which included reassurances over noise, air quality and carbon emissions, was ultimately shaped by two fractious days of rows in the Cabinet and late-night deals.

At a cabinet meeting three days ago, both Gordon Brown and Mr Hoon set out the economic argument for Heathrow expansion but their presentation was interrupted. Two of the dissenters were the Environment Secretary, Hilary Benn, and the Climate Change and Energy Secretary, Ed Miliband. Other ministers joined in, concerned the Government's credibility on global warming would crumble at the first major test if the expansion of aviation, the fastest growing source of carbon emissions, was allowed.

Dissenters included the Leader of the House, Harriet Harman, and Skills Secretary, John Denham. They were joined by Douglas Alexander, a close ally of Mr Brown. As patience wore thin, Mr Brown broke up the meeting, with the final package undecided. But he had no intention of allowing delays over the decision, which had already been put off once, to limp on any further.

He ordered the main players to come up with a package that would help satisfy some local campaigners and the green lobby. While guarantees on air quality and noise placated Mr Benn, it was Mr Miliband who proved more difficult to appease.

He spent Wednesday with the Transport Secretary, refusing to budge over his concerns that the expansion would scupper his forthcoming "carbon budget" designed to put Britain on track to meet its target of an 80 per cent carbon emission reduction by 2050. In the end, sources close to Mr Miliband say he won concessions. He negotiated for the third runway to initially run at half-capacity, limited to an extra 120,000 flights, and he secured a guarantee that carbon emissions from aviation would fall to 2005 levels by 2050.

"Ed is satisfied. The business lobby will effectively get half a runway," said a source familiar with the talks. "BAA won't be happy but we couldn't make an announcement that would blow our carbon budget straight away."

Direct action is already slated for tomorrow, when a "flash mob" of protesters will descend on the departure lounge of Terminal 5. The formal lodging of legal action is likely to be only days away. Residents and environmentalists plan to use Heathrow's breaching of EU limits on air quality as grounds for a judicial review. Should that fail, protesters will be able to voice their opinions at a public inquiry into the BAA planning application.

The Government faces further embarrassment in the Commons. The Conservatives are keen to force a vote on the issue but are planning how they can attract maximum support from the Labour benches. This may mean a back-room deal to allow the Liberal Democrats to take the lead in forcing a vote. A Labour rebellion of 32 votes would defeat the Government.

Support for the third runway, even with the package of sweeteners, including a high-speed rail link to St Pancras and the abandonment of immediate increases to flights, could affect the next election. With the Tories repeating their opposition to the third runway, the election could become a referendum on the project. Backbenchers have already spoken to Mr Brown of their fears of losing their seats.

Some believe the Government's determination to proceed with the third runway was bolstered by the return of Lord Mandelson to the Cabinet. While his support for the economic case for expansion stiffened the resolve, Mr Brown drove the support. He has supported expansion since it was proposed in 2003. And he is reluctant to concede the decision could damage the party.

Others believe Mr Brown wanted to show Labour was still making difficult, long-term decisions. "This is about showing, going into a next general election, that this is a government that has not run out of steam and is still relevant," said a senior party figure.

Cleaner aircraft: Will they arrive on time?

The idea of cleaner and quieter aircraft is at the heart of the Government's case for having a third runway at Heathrow. But what improvements can be made in aircraftengines which, however you look at it, will continue to burn fossil fuels, produce waste gases and create noise?

Quite a lot, actually, the British aviation industry believes. It has set up an initiative called Sustainable Aviation, which has brought together the UK's leading airlines, airports, aerospace manufacturers and air navigation service providers, who are committed to delivering "significant reductions in carbon dioxide emissions, nitrogen oxide emissions and aircraft noise" over the next 15 years. The strategy aims to limit climate change impact by improving fuel efficiency and CO2 emissions by 50 per cent per seat kilometre by 2020 compared with 2000 levels; to improve air quality by reducing nitrogen oxide (NOx) emissions by 80 per cent over the same period; and to lowering the perceived external noise of new aircraft by 50 per cent.

Last month, Sustainable Aviation announced a plan that it said would allow CO2 emissions to fall to 2000 levels by 2050, after peaking around 2020. It said it could do this by improving airframes, engines and technologies for wings, which are expected to reduce CO2 emissions by 62 per cent compared with a "constant technology" baseline. A further 10 per cent reduction was envisaged from improved air traffic management and operations by 2020, while lower carbon alternative fuels were expected to provide a further 10 per cent reduction in CO2 emissions from 2030.

But many observers do not agree that this will be possible in the time frame envisaged. "There's some good stuff going on... but a lot of it is a long way off," said Richard Dyer, aviation campaigner for Friends of the Earth. "We're still building jumbo jets, and they were first built in 1969... It's good that this is being looked at, but some of it is wishful thinking and I'm not convinced they will meet these targets."

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