RBS plans to cut 180 jobs and offshore more roles to India, it announced on Tuesday. A further 154 contractors will also be axed.
The UK taxpayer-backed bank said some staff would be able to re-apply for different jobs, meaning that it expected a net reduction of 92, with most of the cuts affecting technology roles.
The Unite union labelled the job losses “unjustified”.
Rob MacGregor, Unite national officer, said: “Unite cannot understand how RBS, which continues to be taxpayer backed, can justify hundreds more staff cuts and continue transferring important work out of the country,”
“Unite has called on RBS to halt the offshoring announcements and impose a moratorium on the offshoring of jobs.”
An RBS spokesperson said: “As RBS moves towards becoming a simpler, smaller, UK focussed bank, we’re continuing to restructure our back office support and reducing its size so it’s a better fit for our business.
"Unfortunately, these changes will result in the net reduction of 92 roles. We understand this will be difficult news for staff and we will be offering support to those affected, including redeploying people in to other roles where we can”.
The lender has never turned an annual profit since it was bailed out with £45bn (€53bn) of public money at the height of the financial crisis in 2008.
Last month, Chancellor Philip Hammond said the public should “live in the real world” and accept that the Government could sell its stake in RBS at a loss.
The Treasury bought the shares at 502p each- almost double the 264p level they were trading at on Tuesday.