The government is increasing its pressure on the Anglican Church to agree to rebuild the ChristChurch cathedral and has sent it a cross-party letter.
The future of the badly damaged building has been up in the air for six years. The Anglican Church favours a new building while some heritage advocates wanted the original restored.
The Church Synod is to vote in September over whether the iconic building should be reinstated or demolished.
This week, the government offered the Anglican Church $25 million dollars in funding and loans to reinstate the cathedral. The Christchurch City Council also offered $10 million in funding, subject to public consultation.
The letter was signed by the leaders of National, United Future, the Māori Party, ACT, Labour and the Greens who agreed to support legislation that would help enable the cathedral to be reinstated.
It encouraged the synod to make a "prompt decision" about the cathedral's future.
It said the cathedral was not just a place of worship but also a "Category A heritage building, a tourist attraction in the city, and an important community facility".
The minister responsible for Christchurch's regeneration, Nicky Wagner, said: "we need an agreed solution on its future and we need it sooner rather than later".
She said she believed the letter carried a lot of weight, and strengthened the government's funding offer.
New Zealand First was the only party to refuse to sign it.
Leader Winston Peters said the letter would not achieve anything.
"New Zealand First is not interested in cross-party handholding irresolute statements", he said.
The letter was presented to Bishop Victoria Mathews on Sunday.