New financial powers already agreed for Scotland will be a “considerable challenge” to implement, a Holyrood committee has warned.
MSPs are concerned about the level of information provided by the UK and Scottish governments to help with the provisions of the Scotland Act 2012, including a new rate of income tax.
The new tax rate – due to come into force in April 2016 – means the UK Treasury will deduct 10p from standard and upper rates of income tax in Scotland and give MSPs the power to decide how to raise cash.
But Holyrood’s Finance Committee said there is a lack of clarity about forecasts, particularly with the UK’s Office for Budget Responsiblity (OBR).
Considerable work will be needed by both governments to agree proposals to adjust the block grant allocated to Scotland by Westminster, the committee found.
MSPs also have concerns about “wildly optmistic” OBR forecasts for the land and building transaction tax (LBTT), which replaces stamp duty land tax in April 2015.
They said forecasting for a new landfill tax must be transparent and open.
Finance Committee convener Kenneth Gibson MSP said: “We believe it is essential that there is effective parliamentary scrutiny of the implementation process and, in particular, the way in which the UK Government will adjust Scotland’s block grant to take account of the new financial powers.
“We will continue to closely monitor the accuracy of the OBR forecasts and will take evidence from the chair of the OBR on an annual basis.”
The report concludes: “The committee recognises that there is a considerable challenge for both the UK Government and the Scottish Government in implementing the financial provisions of the Scotland Act 2012.
“Nevertheless, it is essential that there is effective parliamentary scrutiny of the implementation process.
“The committee is concerned about the level of information being provided by the two governments as the negotiations progress.
“At the same time, the committee welcomes the commitment of the Scottish Government to consult with the Scottish Parliament on the adjustments to the block grant and emphasises the need for sufficient time to be made available to allow the committee to carry out effective scrutiny of the proposals.”