The gas and
oil industry has voiced concerns about a proposed change to air passenger duty.
A tax on helicopter flights used to fly workers to offshore drilling platforms has been proposed as part of a UK government consultation.
The oil industry claimed that the "huge and wholly unexpected" tax, which would seen helicopters put in the same tax bracket as private jets, would have a big impact on businesses.
Oil & Gas UK, the trade association representing the offshore sector, said plans to extend air passenger duty (APD) to cover helicopters could cost energy companies in excess of £165 million a year.
It added that this is on top of the £50 million that energy companies already stand to lose as a result of the windfall tax announced as part of the Budget.
"It's not as if people can use alternative forms of transport getting to and from offshore installations," said Robert Paterson from the trade association.
However, the treasury said that no decision has yet been made and that it welcomes views on the issue.