NHS Greater Glasgow and Clyde along with other health boards is implementing a new agreement with staff to harmonise payments for on-call staff.
The agreement has measures in place to allow boards to minimise any loss of earnings for workers.
However, it is understood the board has not taken the correct steps to ensure that theatre nurses at Gartnavel hospital do not lose out.
It is believed nurses could lose between £200-£300 each month
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under the new agreement. Staff have refused to provide on-call cover this weekend in protest over the loss of earnings.
Sources said there was a "high likelihood" of staff being asked to provide on-call cover over the weekend for surgery.
The health board said contingency plans were in place to ensure the on-call service would be provided.
A spokeswoman for NHS Greater Glasgow and Clyde confirmed it was working with the union to resolve the issue.
The spokeswoman for NHSGGC said: "Across Scottish health boards a new national on-call agreement is being implemented.
"Along with other Scottish Health Boards NHS Greater Glasgow and Clyde is implementing this national on-call agreement with our staff-side partners.
"A local issue at Gartnavel General Hospital is being discussed with staff-side partners.
"We have contingency arrangements in place at Gartnavel General Hospital this weekend to ensure that the service can be provided if required."