The speed limit on Richmond Hill has been raised to 40mph.

Monitoring will continue with a view to returning the speed limit to 50mph this week if the surface continues to hold up well, the Department of Infrastructure said.

The 30mph limit was introduced in December after recently laid surface chippings came loose.

With some drivers failing to stick to the new limit, the overtaking lane was closed. It reopened at the beginning of this month when the DoI claimed the warmer weather had made the surface more stable. It said a long-term solution is still being assessed.

Police say unmarked cars will be checking that drivers comply with the speed limit.