Has Boris Johnson ditched a pre-election airport promise?

Exhibit A
Conservative Leader of Dartford Council, Jeremy Kite: “When I spoke to him [Boris Johnson] during his campaign he assured me north Kent was not an option [for a new airport].”

Exhibit B
Boris Johnson’s staff: “It is too early to identify particular sites and to confirm or deny north Kent is an option.” [News Shopper]

So that’d be saying one thing before polling day and then doing something else afterwards by the looks of it. A bit of a habit really.