"It will do this at scale and pace so we can build our way out of the national housing crisis."
The Herald earlier reported the authority was expected to take control of 12 to 15 major Auckland housing and transport developments.
The first, which has already been announced, is on the Unitec/Wairaka site, where 3000-4000 homes will be built on 29 hectares.
Another will be along Dominion Rd, which is part of the proposed route of a light rail line to Mangere.
For some large and important developments, the UDA will have the power to shorten planning and consenting processes, finance construction, reconfigure public reserves and bring together separate land blocks so they can be offered as a parcel.
"This is a huge opportunity to massively increase the supply of housing in our fastest-growing cities, that was not previously possible because of the regulatory log jam created by our planning laws," LGNZ's Cull said.
"Local government has worked closely with the minister on this package of reforms, to ensure that we can kickstart development in a way that works best for our communities."
The authority would focus on building on land, which "may have difficult, poor quality, ageing or at-capacity infrastructure, making it difficult to develop", the LGNZ said.
State housing landlord Housing NZ, its subsidiary the Hobsonville Land Company, and the KiwiBuild Unit working on building 100,000 new houses for first-homebuyers will now brought together under the oversight of the UDA.
Glenn Barclay, from the Government workers union, the Public Service Association, cautiously welcomed the new authority.
"As more details of the transition and the legislation that will empower the new entity of HUDA emerge, we will be carefully monitoring the impact on our members in what is being positioned as a 'growth phase'," he said.
Twyford said the UDA would still consult with local government, iwi and the private sector on projects.
The Government plans to introduce legislation setting up the new authority to parliament in 2019. The first projects are expected to be up and running by 2020.
"I look forward to public submissions as we work through the detail of the new authority during a full select committee process," Twyford said.