A 4km section of Auckland's Northern Motorway will be closed five nights a week for the next four months, starting this Sunday.

The New Zealand Transport Agency says the motorway will be closed between Upper Harbour Highway/ Constellation Drive and Oteha Valley Rd from Sunday to Thursday between 9pm and 5am.

NZTA advises motorists to plan ahead and allow more time if travelling at night on the Northern Motorway in coming months.

We thank you in advance for your support, and apologise for any inconvenience this work may cause

The night time closures will allow crews to start preparations for the Northern Corridor Improvements (NCI) project, due to get under way later this year.

The crews will be resurfacing the motorway, painting new line markings and relocating the median barriers and overhead gantry boards, says the agency's senior manager project delivery Chris Hunt.

The repainted lanes will be narrower, so as the work progresses along the 4km stretch of motorway the speed limit will be reduced to 80km/h.

"The work is being carried out at night to reduce disruption and delays on the roads and motorway during the busiest parts of the day. Closing the motorway ensures the safety of our crews working at night and all other road users," says Hunt.

The closures will apply to all motorway lanes and the on and off ramps between the two interchanges, including all ramps at the Greville Rd interchange.

However, vehicles will still be able to travel northbound from the onramps at Oteha Valley Rd, and travel southbound using the Upper Harbour Highway/Constellation onramp to the city, as well as drive along Greville Rd itself.

There will be separate signposted detours for north and south-bound traffic.

"Vehicles will be directed along the same detour routes every night, making it easier and more familiar for people who travel regularly at night. But drivers will need to plan ahead and allow more time for their journeys.

"We thank you in advance for your support, and apologise for any inconvenience this work may cause," says Hunt.

The NCI project will build a new motorway connection between SH1 (Northern Motorway) and SH18 (Upper Harbour Highway) to complete the Western Ring Route, upgrade Upper Harbour Highway, add new motorway lanes to SH1, build an extension of the Northern Busway and add more than 7km of new walking and cycling paths.

"The project is an important link in helping to realise the full benefits of the Western Ring Route by giving people an alternative route to State Highway 1 and the Auckland Harbour Bridge. It will also create better travel choices for walkers, cyclists and users of public transport," says Hunt.

The NCI project will be completed in stages over the next three years.