Government to give go-ahead to "green Heathrow"

The government will this afternoon give the go-ahead to controversial plans for a third runway at Heathrow, unveiling plans for a new high-speed rail link and strict carbon emissions rules in the process as it seeks to minimise the environmental criticism that will be levelled at the decision.

Transport minister Geoff Hoon will formally announce approval for the third runway in the Commons at 12.30pm, defying environmental critics who claim the expansion will undermine the government's climate change efforts and result in breaches to EU rules on noise and air pollution.

However, following long-running divisions within the cabinet, a number of " green sweeteners" have been secured that will be announced alongside the expansion plans, including a new high-speed rail link connecting Heathrow to Birmingham and the Eurostar terminal at Kings Cross St Pancras.

The new link is unlikely to prove as ambitious as that recently flagged by transport minister Lord Adonis, which would have seen a 12 platform rail hub built at Heathrow. But ministers claim it will slash journey times to the North West by providing an alternative to the congested sections of the West Coast mainline around Birmingham.

The new rail infrastructure is also expected to help curb air pollution from traffic around the expanded airport.

Tough new rules on aviation carbon emissions, noise pollution and air quality are also to be introduced, forcing airlines to only use the most fuel-efficient planes in their fleet on the new runway and effectively requiring airport operator BAA to curb flight numbers if EU rules on air and noise pollution are breached.

According to reports in The Guardian, the measures have done enough to secure the support of environment secretary Hilary Benn who had been the cabinet's most vocal critic of the proposed expansion.

However, the "green sweeteners" will not satisfy long-term opponents of Heathrow expansion and both the Tories and the Liberal Democrats have signalled that they will continue to oppose the plans.

A legal challenge to the planning approval decision is also expected within days from a coalition of green groups, while Greenpeace has vowed to oppose the project at every turn, most notably through its move this week to buy up a parcel of land where the third runway will be built and sell it to thousands of campaigners, making it harder for the government to impose compulsory purchase orders.