Waka Kotahi NZ Transport Agency is calling for registrations of interest for a new Waitematā Harbour crossing that will connect Auckland's city centre and the North Shore.

The registration of interest opened today and closes on June 2.

The Additional Waitematā Harbour Connections project is looking for reliable, efficient, and sustainable transport options to move Aucklanders across the harbour.

The project a part of the latest phase in developing Auckland's growing rapid transit network and is expected to be city-shaping.

"This work is an incredibly important part of the commitment to help shape Auckland in the right way for future generations. It's about giving people options to choose how they want to move around the city, whether it's by bus, train, car, bike or on foot," said Waka Kotahi general manager Transport Services Brett Gliddon.

Waka Kotahi, Auckland Transport and Auckland Council are partnering on the project.

The preferred recommendation would cover all transport modes - walking, cycling, public transport and driving.

Auckland Mayor Phil Goff says the new harbour connection will be a transformative project for Auckland.

"Just as the Harbour Bridge transformed our city when it was built in the middle of last century, this project will influence how Auckland evolves for generations to come," said Goff.

He said the significance of the project makes it important to work with industry professionals with the right mix of skills, expertise and experience.

"This will be one of the of the largest and most complex infrastructure projects ever undertaken in New Zealand."

Gliddon said discussions with industry professionals both locally and overseas have already begun, many of whom were interested to work on the complex project.

The planning phase of the project would begin in the second half of this year and a preferred way forward would be decided by the end of 2023.

There will be opportunities for stakeholders and communities to give their input with engagement campaigns planned.

"We need to make sure the city grows in the right way to unlock access to growing community, residential and employment hubs, whilst considering urban regeneration opportunities," said Gliddon.

It is anticipated that the large-scale construction of the project could take up to 15 years.

Auckland Transport executive general manager of Planning and Investment, Jenny Chetwynd, said the project plays a pivotal role in shaping Auckland's economy and quality of life.

"This project is another important step in our continued investment in keeping us moving," she said.

The tender and procurement process is being co-ordinated with Auckland Light Rail (ALR) and more information about registrations of interest can be found on the tender website at gets.govt.nz.