In its "Plan for Scotland 2016-2017" published in September 2016, the Scottish government promised it would "use additional income tax setting powers for the first time, in a manner consistent with our objectives of growing Scotland's economy, promoting fairness and providing additional investment in high quality public service".

On 15 December finance secretary Derek Mackay unveiled a budget which Prospect said fell a long way short of this agenda.

"Once again public sector members in Scotland will face the same 1% cap on pay, at a time of increasing uncertainty over inflation and interest rates, and when they are expected to address the surge in work created by the decision to leave the European Union. Prospect believes this is not the way to invest in high quality public service," said the union's national secretary for Scotland Richard Hardy.

The public sector pay policy for 2017-18 published alongside the budget contains the following key elements:

• Support for lower paid staff below £22,000
• Basic award capped at 1% of paybill for those above £22,000
• Progression to continue
• Additional flexibility to use paybill savings to make "affordable and sustainable changes to existing pay and grading structures"
• No compulsory redundancy guarantee agreement.

"We recognise  there are positive differences between the pay agenda for Scottish public servants as opposed to their Westminster colleagues," said Hardy.

"However, with the growing number of uncertainties facing our members, and the Scottish government's stated commitment to invest in public services, we had hoped to see a significant break in the slavish adherence to the 1% cap imposed by the Westminster parliament."

"If the Scottish government is genuine in its stated aim of working with trade unions to build a better Scotland,  it must be much more ambitious in the use of its tax raising powers," he concluded.

Unions and the Scottish government will  produce joint technical guidance based on the public sector pay policy document;  this will be used as a basis for negotiations by employers and unions.