– Sir Howard Davies, Airports Commission
The challenges remain, but the potential benefits, especially in relation to noise and regeneration, appear stronger than for other new hub sites.
We have therefore stated that we will carry out additional analysis of these options, looking not just at the proposal from the Mayor but also those from private sector promoters, to properly understand some of the implications of a new hub airport at those sites.
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.
Boris Johnson has defended his idea of building an island in the Thames Estuary, saying that a third runway at Heathrow would be "obsolete" by the time it was built.
He added that today's report made plain that advocates of this solution were effectively calling for a four-runway Heathrow, which he said would be "environmentally and politically undeliverable".