Ryanair has responded to criticism by Britain's Environment Minister, Ian Pearson, for failing to take climate change seriously.
Ryanair Chief Executive, Michael O'Leary, has described the junior minister's comments as foolish and ill-informed.
It is one of a number of big airlines being accused of not reducing carbon emissions.
Mr Pearson branded Ryanair 'the irresponsible face of capitalism' and warned British Airways was 'only just about playing ball' in the fight to reduce carbon emissions.
In an interview with the Guardian newspaper, Mr Pearson described Mr O'Leary as 'completely off the wall' and stated the attitude of several US airlines was 'a disgrace'.
The minister was understood to be angry with Mr O'Leary's criticism of an EU carbon trading scheme that could increase ticket prices.
The Ryanair chief was reported to have dismissed the scheme as 'just another tax'.
However, a Ryanair spokesman told the Guardian that 'Mr Pearson was sadly misinformed'.
He said Ryanair had spent over '$10 billion on a fleet of fuel-efficient engines which have reduced fuel burn by 45% and cut CO2 emissions by 50% per passenger making Ryanair Europe's greenest airline'.
