Motorists have been warned of “significant delays” on State Highway 1 in Pōkeno after a tractor and trailer rolled.

Both southbound lanes have been blocked by the single-vehicle crash, which was reported about 2.30pm.

The crash near Pōkeno has blocked both southbound lanes, causing delays.

Police say it appears one person has moderate injuries.

Motorists are being advised to avoid the area and seek an alternative route while the scene is cleared.