A public consultation in Scotland on plans to halve Air Passenger Duty comes to a close today (Friday) amid calls for a rethink.
SNP ministers have said they will cut the duty by 50% between 2018 and 2021.
APD rates for the UK currently range between £13 and £146 depending on the distance of the flight and the class of seat.
Ministers hope that reducing APD will increase the number of direct flights to and from Scotland.
But Scottish Labour leader Kezia Dugdale called on the Scottish government to scrap its plans.
Formally replying to the consultation, she said it was the “wrong priority” at a time of public spending cuts and environmental challenges, the BBC reported.
“Cutting APD would be a regressive step that would increase carbon emissions. It won’t make Scotland fairer or greener,” she said.
“Faced with the choice between carrying on with the cuts to schools and local services or using the powers of our Scottish parliament, the SNP must use the powers to stop the cuts.”
Environmental campaigners demanded that the Scottish government rethink the cut, saying it is “inconsistent with Scotland’s climate commitments”.
The Stop Climate Chaos coalition said that the £300 million raises each year from APD at its current level was the equivalent of employing 11,507 nurses or installing solar panels on 60,000 homes.
Airlines and Scottish airports insist that cutting the passenger tax would boost tourism, investment and business activity in Scotland.