Difficulties recruiting bus drivers could stall plans to re-route buses away from College Green in Dublin more quickly.
That was due to begin in the middle of next year, creating more space for pedestrians.
Dublin city council is currently looking for a design team for the long-awaited public plaza in front of Trinity College, with hopes of lodging a planning application next year before starting work in 2024.
But it's thought extra space for pedestrians could be created in the meantime with plans to accelerate the reduction in traffic from the area.
As part of BusConnects, buses will be diverted from College Green and Dame Street on a phased basis from the middle of next year.
Councillors had asked for the process to be speeded up but according to the Irish Times the National Transport Authority has cast doubts on the acceleration plans.
The NTA says all bus operators are having major difficulties recruiting drivers, impacting the operation of existing routes and the introduction of new ones.