The First Minister made the commitment at the launch of the Scottish National Party's general election manifesto.
The statement echoes the First Minister's comments made to Prospect and other civil service unions during a recent meeting.
"Prospect has been at the forefront of calls for Scottish ministers to change the direction of pay for a number of years," said Richard Hardy, national secretary for Scotland.
"It's very much to be welcomed that in the manifesto for the Westminster elections the SNP has indicated that it is now willing to change direction.
"However, the change will not impact members until 2018. With inflation already rising, we will continue to make representations to the Scottish Government about how we address members' concerns now, not next year," Hardy concluded.