Uncertainty hangs over hundreds of HM Revenue and Customs jobs in Dundee, according to union officials.
The Public and Commercial Services Union (PCSU) fears that around 130 jobs may be lost at the Caledonian House tax office, which is under threat of closure.
Existing staff would be paid off or re-located to Edinburgh or Glasgow as part of a UK-wide restructuring process.
As well as taking money and jobs away from Dundee, union officials say the move could lead to increased tax evasion locally.
The Courier also understands that around 600 HMRC employees based at Sidlaw House will be given different roles in Dundee’s Department for Work and Pensions office by 2017.
This move would coincide with the roll-out of universal credit, which will re-place the existing tax credits system.
The city’s HMRC staff have been told that there will be an announcement on November 12 with further details on the changes.
Hamish Drummond, Scotland East branch secretary for the PCSU said: “There have been indications that the plan for Scotland is to have two HMRC sites, one near Edinburgh and one near Glasgow.
“As a trade union, we’re not accepting a closure as inevitable closing the office in Dundee will be bad for the city.
“We’ve got 130 staff working here and it’s not clear what would happen to them yet. Some may retire, others may seek employment elsewhere or there may be an offer of alternative employment down in the central belt.
“This would mean a chunk of money will be lost locally. It also means that people may feel they’re not being watched any more as there would be no tax office here.
“The situation at Sidlaw House is different the staff there deal mainly with tax credits, rather than income tax.
“They would remain in Dundee, but would have a different employer the DWP. We will be seeking the best possible terms and conditions for the transfer.”
Mr Drummond added that the Fife HMRC office in Glenrothes is scheduled to close.
Most of the 20 or so staff have already been offered alternative employment or taken voluntary redundancy, with no one “forced out”.
An HMRC spokesman said: “HMRC has set out a provisional timetable for announcements in every country and region in the UK to be made in November, explaining how the overwhelming majority of our people will either move to a regional centre or one of a network of transitional sites, over the next decade. The changes are one of the building blocks of transforming HMRC into a smaller, more highly-skilled organisation, that provides better, more modern services and value for money for taxpayers.”