Boris Johnson has put in a final submission for a new airport to the Airports Commission - the body deciding how to expand air capacity in the South East - in a bid to get a new airport built in the Thames Estuary.
The Mayor claims a new airport on the Isle of Grain would boost the economy by £7 billion each year and create thousands of jobs, but his plans have attracted criticism in the past.
Yesterday, Medway and Kent Councils, who both oppose the Mayor's plans, published the results of a survey they commissioned that apparently showed five out of six adults would oppose the new airport.
Rival bids include Heathrow and Gatwick airports, each campaigning for a new runway. The Commission is due to make a final recommendation by 2015.
The head of the Whitehall-appointed Airports Commission has indicated that the idea of a "Boris Island" new Thames Estuary airport is still very much under consideration.
Last December, the commission chairman Sir Howard Davies described the estuary plan, supported by London Mayor Boris Johnson, as "imaginative" with the cost possibly as high as £112 billion.
The estuary option did not make the commission's new-runway shortlist published in December, although the commission said it would further study the estuary plan.
But in an interview with the Business Travel News publication due out on Monday, Sir Howard speaks of the possible benefits of an estuary scheme.
London Mayor Boris Johnson has given his blessing to the new six-runway option for a Thames Estuary airport, saying:
A new plan for an airport on the Thames Estuary has been unveiled - with six runways instead of the four originally proposed.
Plans for a Thames Estuary solution to London's airport capacity problems have been dubbed 'Boris Island' after the Mayor expressed his support for them.
The plans have been drawn up by Testrad - the consortium set up by the Mayor to look at Thames Estuary proposals. The new airport would be called 'London Britannia' and sit on a purpose build island off the Isle of Sheppey in Kent.
There are around 500 harbour seals and 200 of the larger grey seals in the Thames Estuary, according to the Zoological Society of London (ZSL) said.
ZSL's conservation scientist Joanna Barker said:
The Thames Estuary has become the focus of a new exhibition.
Film, photographs and paintings are featured at the Museum of London Docklands, which is now celebrating its 10th anniversary.
It opens tomorrow and Martin Stew has had a preview.
The House of Commons Transport Committee has said, in a report today, that the government should reject the Thames Estuary airport plan and expand Heathrow instead.
The plans for a new hub airport east of London, favoured by London Mayor Boris Johnson, are described as far too expensive.
The first video clips of three giant cranes from China as they head into port on the River Thames near Essex. The cranes will aid container shipping once the London Gateway opens later this year.