Allan told OnTheWight that although the landslip didn't look too serious from the photos, it was expected to be across the path of the road by the end of the night.
The road closure will remain in place until Island Roads are advised by the council what actions they are taking to ensure that it is safe to re-open the road.
Residents and businesses around the Island affected by the road closure on Undercliff Drive are being urged to attend an open meeting on Wednesday this week to share their concerns.