Police have moved one of the access points to the Christchurch central business district restricted zone.

The checkpoint on the corner of Cashel and Madras streets has been relocated to the Manchester and Worcester street corners because of a building being further destablisized by ongoing aftershocks.

Senior Sergeant Pete Cooper advises that the cordon shift that was to occur this morning, but was delayed by ongoing safety issues, has now occured.

"I'm asking the public who are accessing the restricted zone to take care, walk in the middle of the road, and observe areas that are further fences off. "