Part of State Highway 7 in the central South Island that includes Lewis Pass remains closed today after a slip on the road.

The slip, just south of the Riordan Creek Bridge, was discovered early this morning and has forced the closure of the highway in both directions between Springs Junction and Island Hills.

No detour is available, and motorists are urged to delay any travel and avoid the area, and NZTA spokesman said. 

Crews are working on options this afternoon to provide access, but an overnight closure may be required.

A further update will be provided around 4pm today.