Motorists are being warned to expect significant delays following a multi-car crash on Auckland's Southwestern Motorway.

The crash has blocked all traffic heading in the northbound lane near the Maioro St offramp.

The New Zealand Transport Agency is warning motorists to expect significant delays and consider an alternate route.

The transport agency is advising motorists on the Maioro St offramp to use the shoulder to pass the crash.

Meanwhile, motorists heading south on the Southern Motorway also face delays. The southbound lane is heavy from East Tamaki to Manukau following a truck breakdown.

The truck blocked the left lane just after the Orams Rd overbridge, and NZTA has advised motorists to expect delays in the area.

The breakdown has now been cleared but congestion is expected.

The crash and breakdown has caused delays on Auckland's motorway network this afternoon. Photo / Google Maps

 

Traffic is also heavy on the Northern Motorway northbound between the Harbour bridge and Upper Harbour Highway.

Traffic is also heavy citybound between Northcote Rd and the Upper Harbour Highway.

The Northwestern Motorway is heavy between Rosebank Rd and Lincoln Rd for those heading westbound.

The Southern Motorway will be heavy at times between Symonds St and Greenlane, as well from Mount Wellington following the truck breakdown as congestion eases.

The Southwestern Motorway is heavy between Walmsley and Massey roads southbound.

Meanwhile traffic northbound is also heavy from Massey Rd to the Mangere bridge.