SPT aims to borrow the majority of the cash needed for the overhaul
A £400m revamp plan of Glasgow's Subway system could see staff numbers cut and the introduction of driverless trains and upgraded stations, it has emerged.
The proposals are contained in a report which is due to be considered by Subway operator, Strathclyde Partnership for Transport (SPT), on Friday.
If approved, SPT would ask the Scottish government for increased funding and also borrow against existing assets.
It believes the plans can deliver huge savings over the next 30 years.
The report outlines options for a £290m overhaul of Glasgow's ageing Subway system with an additional £100m to cover operational costs over the next three decades.
The system, in its existing state, is believed to require about £220m on maintenance work over the same time period, with a further £320m in operational costs.
SPT believes that a major revamp could cut running costs in the next 30 years to £100m.
Stations would be upgraded as part of the £390m revamp
Scotland's largest transport authority will be asked to back the improvement plans in principle, paving the way for far-reaching changes to infrastructure and staffing.
Driverless trains could be introduced on new tracks running through refurbished stations.
These changes would require a 25% reduction in the system's 350-strong workforce.
The report states, however, that there would be no compulsory redundancies as most of the staffing cut could be achieved through retirements as the new system came online.
To pay for the overhaul, SPT proposes asking the Scottish government for an additional £5m a year for the first 10 years of the project.
This would help meet interest payments the authority would incur in borrowing the majority of the cash against the value of existing assets.
Glasgow's Subway system was built in 1896. The last major revamp was in 1977.