A THIRD of Glasgow subway drivers have been re-trained for other roles as the city’s historic underground system moves towards driverless trains.

Strathclyde Partnership for Transport (SPT ) confirmed the number and said options for re-deployment would be available to staff until the rollout of the new system was complete, which she said was,”a number of years away.”

Swiss company Stadler won the tender for the delivery of 17 underground trains in March 2016.

The new carriages can reach a maximum speed of just over 36mph and will be the first in the UK to run automated.

They will initially operate with drivers on board, with full automation expected to follow in 2021 - the system’s 125th anniversary.

Read more: Historic day as new Glasgow Subway trains arrive 

The first of the new trains has already arrived in Glasgow and will undergo a lengthy testing process before it becomes operational.

A spokeswoman for SPT said: “A third of our current drivers have already undergone retraining for new roles in control, operations, and in customer service.  

"We continue to look at future training options for all staff and we are working closely with our trade union colleagues to ensure staff remain informed of the options open to them.”

Glasgow Subway is the third oldest subway system in the world, dating back to Victorian times.

It consists of a running circle measuring 10.5 km in length with 15 stations.

Read more: First look at new high speed bullet trains between Glasgow and Edinburgh 

The new trains will be the same length as the existing rolling stock they are to replace,39 metres, but they will be made up of four-car sets, as opposed to the current three-car sets.

They will also feature an open design with a large proportion of standing room to maximise the space available and improve accessibility for people with limited mobility.