State Highway 25 between Hikuai and Opoutere will be closed overnight after Waka Kotahi said there was further movement under a slip on the road.
Roading contractors were to keep building an access track around the slip this evening.
Earlier today, the road was opened for light vehicle use under stop-go traffic management.
Any decisions on whether to reopen a lane will depend on inspections tomorrow morning.
This morning, drivers were told to expect delays while contractors continue working to stabilise the road and widen the surface.