A CROSS-PARTY group of MSPs has backed the general principles of a new air tax bill – but called for more information on the impact of the move.

The Scottish Government has announced plans to reduce aviation tax by 50 per cent by the end of the current parliament, and eventually abolish it completely "when finances allow".

The reduction in the levy will begin when a Scottish replacement to air passenger duty (APD) is introduced in April 2018 through the Air Departure Tax (ADT) Bill.

All but one member of Holyrood's Finance Committee endorsed the general principles of the proposal in a parliamentary report, but said the absence of supporting evidence "has the potential to undermine scrutiny" of the policy.

Committee convener Bruce Crawford said: "The Finance Committee recognises that the Air Departure Tax Bill is an enabling Bill.

"Nevertheless, we are disappointed by the government's lack of information on exemptions to the tax and on the economic, social, financial and environmental impacts that will result from a 50 per cent reduction in ADT."

However Greens co-convener Patrick Harvie, who was the only member of the committee not to support the general principles of the bill, said: "It's quite clear from the evidence heard by the committee that this policy has zero environmental credibility."