The UK transport secretary has branded government warnings over pollution related to a runway expansion at Heathrow airport "over-cautious".
Geoff Hoon criticised the conclusion of a government-compiled risk register assessing the negative impact that an expansion could have upon the local area and surrounding environment.
He stated: "A risk register is only a snapshot at a particular point in time and should be interpreted alongside other evidence.
"With hindsight, the October entry looks over-cautious," Mr Hoon added.
Several ministers, nearby residents and London mayor Boris Johnson are against the creation of a proposed third runway at the airport, as well as increased use of existing runways.
In other environmental news, Hong Kong's
air quality is so poor that one in five residents is thinking of leaving the city to live elsewhere, according to a new survey conducted by Civic Exchange.