What David Cameron said about a third runway at Heathrow

David Cameron was very clear in 2009: "The third runway at Heathrow is not going ahead, no ifs, no buts.”

But... the Airports Commission has just recommended Heathrow as the preferred site for London's new runway, which leaves the prime minister in a bit of a pickle.

So far he's kept pretty quiet. Downing Street officials said on Wednesday morning that they want to digest the report properly, without making "a snap judgement".

There's a strong economic argument for building an extra runway at Heathrow, which is already London's largest airport, and will create £147bn in growth and 70,000 jobs by 2050.

It would also connect the UK to 40 new destinations.

But while backing Heathrow, the commission, led by Sir Howard Davies, has also left the door open for expansion at Gatwick instead, giving the prime minister a political loophole if he wants to avoid breaking his 2009 pledge not to build at Heathrow, repeated by the coalition government in 2010.

The prime minister is probably keen to avoid the fate that met Nick Clegg after the Liberal Democrats' U-turn on tuition fees.

No ifs no buts: he's going to make people angry either way.

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