The council says that every time a smoker leaves the building for a smoke, it places an unfair extra workload on their colleagues.
They will therefore be asked to sign a contract extending their working hours from 37 to 39.5 hours a week.
Manny Lewis, the authority's head of personnel, said that as part of the drive to eradicate smoking the council and the local health authority had earmarked£10,000 to provide professional counsellors to help people quit.
'We can hardly educate people about healthcare if we allow smoking in our own offices. And why should smokers take breaks which are not allowed to other workers?'
But Pat McMaster, a smoker who works in the property services department, claimed the policy was 'oppresive'. He said: 'When they banned smoking at the desks they gave us smoking rooms, which we accepted. Now those have been taken away and we have to stand outside in the cold. This has nothing to do with health. It is all to do with money. They forget the unpaid overtime we put in.'