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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The former London Mayor also claimed Tony Blair's decision to ignore security advice had "killed 52 Londoners".
The victim, a woman in her 40s from Hillingdon, west Londion, was conned into handing over the fortune to a man who faked his name.
Inspectors found a culture of bullying and major problems with poor ambulance response times at the trust, which is the biggest in the UK.