Barclays is to move its in-house technical support centre from Cheshire, north England to India, in a move which could see many staff lose their jobs.
Barclays current internal help desk is at Knutsford, Cheshire
A total of 140 workers are affected by the move, but Barclays says it will try to redeploy as many as possible within the firm before making any job cuts.
"We see offshore outsourcing as a way of ensuring improved productivity and efficiency," said a company spokesman.
The Amicus union said the business case for moving jobs offshore was weakening.
"There is growing evidence that the case for offshoring has failed, " said a spokesman for the union, which has been at the forefront of campaigns to prevent more finance jobs being moved to India.
"We can only hope that Barclays has not taken this decision lightly and that there will not be more job cuts."
At present if staff have technical problems, they contact the company's Servicepoint help centre at Radbroke Hall, Knutsford, in Cheshire.
Last October, Barclays set up a joint venture with Indian firm HDFC to create a company in Mumbai called Intelenet, which will now deal with problems.
"We are currently holding one-to-one meetings with staff about possible redeployment opportunities," said a Barclays spokesman.
"We cannot say we can provide new jobs for everyone, but there will also be the opportunity for people to go to India to help training staff there."