A section of the A1 near Banbridge will be closed on Wednesday and Thursday night to allow for resurfacing work to be carried out.
The road will be closed off to southbound traffic between Dromore Road and Newry Road.
Traffic will be diverted via Dromore Street, Church Square, Bridge Street, Downshire Road, Scarva Street and Commercial Road.
The close will be between 8:00pm and 6:00am on both days.
Motorists should expect delays.