Budget airline Easyjet has attacked the recent doubling of UK Air Passenger Duty, describing the charge as "an ineffective environmental tax".
Easyjet says the duty is unfair
The carrier said the duty was unfair as it did not apply to freight flights or recognise that some airlines have more efficient planes than others.
Easyjet says its flights are 27% more fuel efficient per passenger than the European airline average.
The airline saw passenger numbers for the last three months of 2006 rise 10%.
It also predicted that its profits for year to December were set to rise by 40-50%, despite the carrier facing a 7% rise in its fuel bill for the first half of its financial year.
Rules doubling the amount of passenger duty people pay when taking flights from the UK came into force last week.
UK Air Passenger Duty now starts at £10 for an economy class flight within the UK or Europe, rising to £80 for a business or first class ticket on a long-haul flight.
However, Easyjet said that by investing in newer planes it had been able to reduce its carbon dioxide emissions by 18% per passenger since 2000.