Academics at the University of Manchester are facing restrictions on access to their research funds.
Until recently, staff have had control over their individual reserve accounts, which are worth millions of pounds in total. Some academics have personally earned the money in the accounts through extra work, consultancy or research.
But under the changed arrangements, which vary from school to school, access to the cash is now being restricted, with some staff being told they cannot spend more than £1,000 per year without permission.
The University and College Union at Manchester believes the changes are a result of the university's recent financial problems. Branch officer David Beale said: "We don't know how widespread the problem is yet, but certainly some of our members feel that the university has suddenly moved the goalposts. The branch now plans to survey our members to assess the extent of the problem."
"We want an assurance that no staff members will be worse off in terms of the extent and quality of the research, conference participation and study-leave activities in which they may be involved."
A spokesman for the university said: "The only formal change as far as 'reserve' accounts are concerned is that schools and faculties now have to budget for the expenditure, so that we can properly manage the finances of the university. They can then spend against that approved budget."
He added that personal accounts were not being frozen, but all staff were being asked to budget for the expenditure.
"This is normal procedure within most major organisations," the spokesman said.