"This is an important milestone in the Christchurch recovery."
The legislation will enable fast-tracking of resource management and consenting, and will also support the creation of a Reinstatement Trust, providing governance and overseeing fundraising, and a joint venture project management company to oversee the reinstatement process.
The Government will provide funding of $10 million, with a suspensory loan of $15m. The work was signalled by the previous Government prior to the election, based on the independent cathedral working group.
Ardern said she expected the reinstatement trust to be incorporated within the next two weeks.
Minister for Greater Christchurch Regeneration Megan Woods said the damaged cathedral represented the "broken heart of our city".
"I'm thrilled this legislation will allow us to get on with the work of getting this local landmark reinstated and back open to the public. All Cantabrians want to see this situation sorted with a sense of urgency and momentum.
"This has been a long and controversial process. What local people want to see is progress and a clear way forward."
She said the legislation was agreed with cross-party support.
"I especially want to acknowledge the previous Minister, Nicky Wagner, for all of her initial work in bringing the various parties together and getting this work under way."
It has been more than six years since the Gothic-style 136-year-old cathedral was badly damaged in the 6.3-magnitude February 22, 2011, earthquake that devastated the Garden City.
The Cathedral is listed Category 1 with Heritage New Zealand, reflecting its regional, national and international significance.
A recent church-commissioned survey found the Christchurch community was evenly split on whether the cathedral should be rebuilt or demolished.
