Chancellor's Heathrow expansion plan hits turbulence over climate

Reeves's third runway pledge as part of push for growth triggers criticism

- Heather Stewart Jessica Elgot Helena Horton

Rachel Reeves caused a furious backlash yesterday as she insisted that a third runway at Heathrow was "set up for success" despite scepticism in Whitehall that the plan could be reconciled with the UK's climate obligations.

The chancellor made throwing the government's weight behind Heathrow expansion the centrepiece of a major speech on growth.

"As our only hub airport, Heathrow is in a unique position - and we cannot duck the decision any longer," she said, claiming that "the case is stronger than ever".

Reeves struck an optimistic tone on the UK's economic prospects after accusations that she had been too gloomy during Labour's early months in power and more recent government bond selloff jeopardised her tax and spending targets.

"Everything I see as I travel around the country gives me more belief in Britain and more optimism about our future - because we as a country have huge potential," she said.

But the Heathrow plan - meant to signal the government's determination to push through objections and back major infrastructure projects after two decades of uncertainty around the project - was immediately questioned by some government insiders.

Reeves said the government would draw up a new airport national policy statement in the coming months to ensure the third runway was "in line with our legal, environmental and climate obligations".

But some Labour sources insist that this means the airport's expansion will never happen - because it would trash the government's emissions targets.

Sources stressed that future consent would be granted only if the Department for Transport met its carbon budget - a small victory for Ed Miliband, the energy secretary, who has repeatedly pointed out how tight these budgets are without allowing for any airport expansion.