An on-the-ground investigation will begin into a slip which caused significant damage to State Highway 4 south of Raetihi last month.
The site, in the central North Island, remained active and continued to move in the weeks following the incident, and geotechnical engineers had been assessing the affected area remotely using drones, the New Zealand Transport Agency said in a statement.
The engineers have since confirmed that the site has been stabilised and is safe for ground crews to enter.
Work will now begin on assessing short-term options for reinstating the road, NZTA regional transport systems manager Mark Owen said.
"Until our ground crews have fully assessed the site, we won't know exactly what this will look like or how long it will take, but we expect to be able to announce a temporary option soon," Mr Owen said.
"Public safety is paramount, so any temporary option will require careful and constant observation. If the road is deemed unsafe for vehicles at any time, it will be closed immediately and possibly at short notice.
"Due to the scale and complexity of the slip, a long-term solution will take more time."
The NZTA will work alongside the Ruapehu District Council in the coming weeks to install new signage reminding travellers that the Raetihi township remains open for business.
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