New London airport plan shelved

It's a scheme which has become known, and in some quarters, derided, as Boris Island.

London mayor Boris Johnson was a big fan of a plan to build a new four-runway airport to the east of the capital, in the Thames Estuary.

But an official body investigating how to increase Britain's airport capacity has grounded the idea.

A "network of competing airports" is now the preferred solution.

That could mean expanding Heathrow to the west of London, or Gatwick to the south.

Other cities around the world face a similar dilemma.

We discuss that dilemma with Rob Gray, co-ordinator of the Back Heathrow campaign - which supports expansion at Heathrow - and John Stewart, chair of a lobby group called Airport Watch, which is opposed to what it calls "unsustainable" aviation expansion.