Tyne and Wear Metro trains would keep running if parts of the North East were put back into lockdown - but passengers from different areas might have to obey different rules.
Spikes in COVID-19 cases across the region have sparked warnings that tougher restrictions may be put in place, including local lockdowns.
This could mean new rules on who can use public transport.
At the height of the national lockdown only essential journeys were allowed and operator Nexus said that if an area were put back into this status then it would expect similar restrictions.
The layout of the Metro system though could lead to a situation where passengers are allowed to travel through lockdown areas so long as they don't leave the train.
For example, if Gateshead was the only borough to have new restrictions imposed then someone could still potentially get the Metro from Sunderland to Newcastle for a non-essential trip.
The spokesperson also said that the Tyne and Wear Metro was a "COVID-secure" environment with extra cleaning of trains, hand sanitiser at stations, staff in face masks and guidance on social distancing meaning "people can use Metro with confidence".
The town of Bolton in Greater Manchester has had some lockdown restrictions reintroduced.
Advice from Transport for Greater Manchester states that people living in Bolton must not use public transport except for essential travel such as going to school, work or medical appointments..