Cameron promises Heathrow decision by Christmas amid Tory civil war

Decision is particularly difficult for PM because he unequivocally ruled out a third runway in 2010, and now faces prospect of cabinet resignations

David Cameron will resolve his dilemma on whether to back a third runway at Heathrow by the end of the year, but faces the prospect of cabinet resignations and having to rely on Labour support if the government decides in favour.

The prime minister said on Wednesday that he had yet to study the recommendations of the Davies commission, which strongly backed expansion at Heathrow.