SNP ministers have been urged to come clean over plans to “save money” by scaling down the buildings it owns.

The Scottish Government said it was reviewing its buildings to ensure they are “of the right size to meet our changing needs and net zero ambitions” and allowing civil servants to continue working from home as part of a hybrid model.

The move comes as Deputy First Minister Shona Robison, who is also the Finance Secretary, gears up to deliver her first Budget.

Ms Robison warned in May that the funding gap was likely to be £1 billion in 2024-25, increasing to £1.9 billion by 2027-28.

Speculation has mounted that the Scottish Government could hike tax for higher earners after pointing to a new 44p income tax band on those earning between £75,000 and £125,140 a year to raise £200 million.

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In a “mandate letter” accompanying the Programme for Government, Humza Yousaf said his deputy FM had agreed the 2024/25 Scottish budget would be underpinned by tax measures which improved “fiscal sustainability”.

He said she would “use our tax powers in the setting of the 2024/25 Budget to further progress delivery of the most progressive tax system in the UK by making tax policy choices that are informed by public and stakeholder views”.

Ms Robison has suggested that the strategy is also “about making sure that government and public bodies are the right size for the job that they have”.

She added that elements such as “more digitization” and “people working from home more” will mean that “we won't need the same configuration of buildings and potentially having the right size in the right place”.

David Longsdale, director of the Scottish Retail Consortium has warned that “it matters profoundly that Scottish ministers succeed in reducing the cost of government”, claiming that “otherwise taxes on households and firms might rise and the recovery and economic growth, which is already lacklustre, could be held back”.

But SNP ministers have been urged to be transparent about their intentions.

Scottish Conservative shadow secretary for business, economic growth and tourism, Murdo Fraser, said: “Shona Robison and her SNP colleagues appear to be asleep at the wheel when it comes to tackling Scotland’s finances.

Read more: Humza Yousaf urged not to hike taxes to plug £1billion hole in budget

“They must be fully aware of how working patterns have shifted since Covid hit, but they appear not to have thought about the costs of continuing to run buildings with fewer civil servants occupying them.

“It is no wonder the SNP has created a £1 billion hole in Scotland’s finances – and appear to only be trying to fill it by increasing people’s taxes – when they haven’t bothered to do these basic sums.”

Scottish Labour finance spokesperson, Michael Marra, said: “The SNP is keeping taxpayers and workers in the dark about their plans.

“From job losses to tax hikes, they must be honest about the painful choices they are planning to make.”

Scottish LibDems finance spokesperson, John Ferry, said: "If flexible working is here to stay then the Government will need to work out how to put its large estate to good use, perhaps by co-locating other public services alongside civil servants or disposing of buildings which are no longer required.

"In the middle of a cost-of-living crisis both job cuts and tax rises would damage the economy and hurt households so the government will have to be creative in how it tackles its budget pressures.

Read more: Robison hints at cuts as she moves to tackle spending gap

"All of these problems are more acute because the Scottish Government have so utterly failed to get the economy out of its current crawl. Businesses and households can have little confidence that SNP ministers hold the economic answers they are looking for."

A Scottish Government spokesperson said: “The Programme for Government committed ministers to delivering a more efficient approach to public sector property management by working with our partners through the new single Scottish estate programme.

“This will save money and reduce the public sector estate, enabling progress towards our net zero targets.

“Our own estate is also under review to allow us to plan for affordable, inclusive, accessible, modern, secure, energy-efficient buildings of the right size to meet our changing needs and net zero ambitions, as well as to ensure best value for taxpayers’ money.

“The Scottish Government is committed to flexible hybrid working for our workforce, enabling staff to work from a range of settings that ensures business needs are met.”