MOTORISTS in Newport could face weeks of frustrating tailbacks as new traffic- lights cause chaos around one of the city's busiest roundabouts.

The newly installed traffic-lights at the Pont Ebbw roundabout are being blamed for long queues along one of Newport's main roads this week. Motorists have been stuck in queues that have left them taking half an hour to travel less than a mile along Cardiff Road.

The new lights are part of the ongoing construction of the Southern Distributor Road, which is designed to take traffic away from the centre of Newport.

The Tredegar Park roundabout, by the M4, will be the official end of the SDR, which starts at the Coldra junction.

Road builders Morgan Vinci said motorists will have to allow time for the new lights to bed in.

Peter Frood, project manager for the SDR, said the lights have switched from an initial timer system to a vehicle-activated function, where the lights change according to levels of traffic.

He said the new function should relieve some congestion, but the increased traffic generated by the roadworks meant there would be some delays until the road opens.

Mr Frood said: "At the moment, while the road is being completed, there is a lot of traffic.

"The lights are going through a settling- down period. We need the traffic to settle down and allow for the lights to bed in.

"It is a very busy junction and roundabout. "When much of the traffic from Cardiff Road is turning right, the lights create a break so the traffic from the SDR and Duffryn can get on the roundabout.

"Unfortunately it's not an exact science, it depends on traffic flow." Mr Frood said there were no plans to introduce a system similar to the Coldra and Malpas Road motorway roundabouts, where lights are only used at peak times. "At the moment they are there full time.

"Once the traffic settles down after the road is opened, then these things can be reviewed again."