Prime Minister John Key says Cabinet will be briefed on Monday on the Canterbury earthquake by Civil Defence Minister John Carter.
Mr Key returned to Auckland on Saturday night after visiting Christchurch following the magnitude 7.1 earthquake, but says he will return there with a group of ministers on Tuesday or Wednesday.
He told Morning Report that by then, they will have a better idea of how vast the reconstruction will be.
Mr Key said the priority is firstly, people's welfare and secondly, ensuring buildings are safe.
He said the army is available to help and he expects soldiers will be dispatched for back-up support at some point.
Mr Key said the Government may contribute to a mayoral relief fund, but the major cost will be the restoration of infrastructure.
He said the Government will reprioritise its plans for infrastructure, to accommodate the restoration effort.
Minister shocked by scale
Mr Carter says he's shocked at the scale of the damage.
The minister, who also visited the region on Saturday, says the cost of the damage to homes, public buildings and infrastructure is likely to run into billions of dollars.
He says the next phase will be restoring normal life in Canterbury, and getting utilities, schools and businesses running again.
Mr Carter says he is in close contact with the region's mayors and has assured them they have the Government's full support.
Goff taken aback
The leader of the Opposition, Phil Goff, has visited the destruction in Christchurch and says he is stunned by what he has seen.
Mr Goff has been looking at the damage in suburban areas surveying a row of shops that have been "just about totally devastated" by the tremor and other shops that will need to be demolished.