A fresh slip has blocked State Highway 1 south of Kaikoura after heavy rain from ex-Cyclone Cook.
The new slip may close the road for two or more days, NZTA said.
The road was closed about 1pm today after the slip brought down several thousand cubic metres of debris.
The large slip is about 3km southwest of Peketa, and north of an old slip site at Rosy Morn.
The highway was reopened after heavy rain yesterday between 3 and 6pm and reopened again this morning.
The inland road to Kaikoura, Route 70, via Waiau and Mt Lyford, remains open.
Steve Mutton, NZTA earthquake recovery manager, said people should check the agency's traffic and travel pages for updates before they head to Kaikoura over Easter.
"There are electronic signs at Waipara advising if the State Highway route is closed and another sign north of Cheviot.
"If people make it to Cheviot and find the State Highway is closed, they can take the Leader Rd to reconnect with the inland road via Waiau."
• The inland road, Route 70 via Waiau and Mt Lyford, is open 24/7.
• When it is open, the State Highway to the south of Kaikoura is open daylight hours only, 7 am to 6pm.