Construction has started on the first section of New Zealand’s NZ$709.5m ($506m) Puhoi to Wellsford road, which is one of the government’s Road of National Significance.

The 18.5km Puhoi to Warkworth road will be a new motorway between Auckland and Northland.

Transport Minister Simon Bridges said: “Extending the Northern Motorway between Puhoi and Warkworth will enhance inter-regional and national economic growth and improve the reliability of the transport network between Auckland and Northland.

"It will also support population growth, connecting the expanding Warkworth area which is expected to grow to 20,000 residents in the next few decades."

“It will also support population growth, connecting the expanding Warkworth area which is expected to grow to 20,000 residents in the next few decades.”

Last month, the NZ Transport Agency signed a contract with the Northern Express Group for the Puhoi to Warkworth motorway project.

The road project is being delivered through a public private partnership, which is the second for a state highway, after the Transmission Gully motorway project in Wellington.

Work on the project’s second stage between Warkworth and Wellsford is also currently underway.

Bridges said that the NZ Transport Agency is undertaking investigations and will soon share an indicative route with the public early next year.

Both the projects are expected to reduce the overall travel time between Auckland and Northland.

Bridges added: “It will also create a better freight connection for Northland to the Upper North Island freight 'Golden Triangle' of Auckland, Waikato and Tauranga.”

The road is expected to open to traffic in late 2021.