Zac Goldsmith, Conservative MP and environmental campaigner who has threatened to quit over a third runway at Heathrow, told BBC Radio 4's Today programme:
"We haven't just lost Justine Greening from this department, we have also seen Theresa Villiers moved out, both of whom were absolutely rock-solid on this issue in terms of defending what is still the Government's line officially.
"I think their movement out of the Department of Transport shows the Government is at least trying to open the door to the possibility of a third runway."
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A terror suspect accused of deliberately crashing a car outside the Houses of Parliament is understood to be from the Birmingham area.
Meanwhile, Vienna has displaced Melbourne as the world’s most liveable city.
Scotland Yard said the driver, a man in his twenties, was arrested at the scene by armed officers on suspicion of terrorist offences.