The A4042 in the southbound direction between Pontypool and the Court Farm roundabout will be closed overnight, every night, until the end of this week.
The road will be closed both southbound between the Court Farm Roundabout – near the Horse and Jockey pub – and Pontypool Roundabout – also known as the McDonald’s Roundabout.
The dual carriageway is undergoing essential repairs closing it completely in both directions between 7pm and 6am daily, until December 20.
The dual carriageway will also be closed in the northbound direction between 7pm on December 19 and 6am on December 20.
After 6am, one lane opens, with the other closed, and so drivers should expect delays in the area, especially during rush hour.
Traffic Wales have confirmed that diversions will be in place for the duration of the road closure and advise drivers to allow extra time for their journeys.