David Cameron today ruled out building Boris Johnson's airport in the Thames Estuary.
Asked by the BBC whether he would go ahead with Boris Island he replied that:
"Boris is a great mayor of London doing an excellent job, but building airports is not his responsibility."
During his visit to Kent, Cameron said that Boris Island was "not our policy" and repeated his opposition to Heathrow.
Cameron's comments are a huge embarrassment to the Mayor who reportedly said that the airport was the biggest and bravest thing he could do.
In the past year Boris has made a high profile visit to the site of the airport, commissioned a lengthy feasibility study and set up a steering committee to take charge of the project.
In the process he has created big divisions within his own party, and caused embarrassment for his party leadership both nationally and locally.
The Mayor has repeatedly said that there should be further airport expansion in the South East.
Now that his fantasy airport is sunk, he must spell out exactly where that expansion should take place.