By Charles Maggs Follow @charlesmaggs
Boris Johnson has again attacked the government's handling of the disputed third runway at Heathrow, claiming the UK is on track for "economic catastrophe" as a result.
In a speech at City Hall the London mayor said No 10's response to calls for a decisive new aviation strategy had lacked the urgency that the situation required.
"The government programme to address the looming aviation capacity crunch in the UK is far too slow and I am hugely concerned that their intended timetable sets a course for economic catastrophe," he told journalists.
He suggested that not addressing the issue of flight capacity was putting Britain at a competitive disadvantage.
"This continued inertia is being fully exploited by our European rivals who already possess mega hub airports that they intend to use to erode our advantage," he added.
Despite being critical of the timescale of the government's review into the matter - which isn't due to report back until after the next general election in 2015 - he said he will continue to assist in its work.
"But the urgency of the situation and the lamentable attention that the Government has paid to this pressing issue has forced me to accelerate the work that I will do to develop a credible solution," Johnson said.
It has been two years since the mayor first proposed the building of a new airport in the Thames estuary, popularly dubbed 'Boris Island', and it's an idea he continues to advocate.
He estimates that the cost of such a project to be around £80 billion, considerably more than the £10 billion which Heathrow expansion supporters believe a third runway would cost.
He also argued in favour of more flights going to Gatwick and Luton and suggested that an expansion to Heathrow would only provide a short term solution.