A wide load vehicle has brought down power lines in Te Horo, blocking parts of State Highway One.

The large vehicle made contact with some overhead wires south of Otaki and the lines are now down across the road, police said.

Police are on their way to the scene to ensure the road is safe and the area has been blocked off.

Motorists are asked to be wary of traffic backing up in the area and to watch out for lines across the road near the scene.