Mr Goff said the issue was around existing or potential shortages of building materials and skilled labour as well as land suitable for rebuilding.
"The Government needs to prepare for that and so far they haven't."
But Mr Key said his Government was tackling those issues.
"Council has assured us there is a range of sections coming available and we have the capacity under Cera (Canterbury Earthquake Recovery Act) to fast track that if we need to.
"The Government itself, by virtue of South Canterbury Finance, has inherited a lot of land, there's quite a number of subdivisions actually available there."
Mr Key said the Cabinet had some general discussions with the Christchurch City Council about "what might happen to a specific group of older New Zealanders who might find it very difficult to fund themselves if there's an increase in price".
Meanwhile, he also said the insurance issue was at least partly due to some insurance companies experiencing difficulty in securing financial backing from the giant international reinsurance companies at reasonable prices.
Earthquake Recovery Minister Gerry Brownlee is in Monte Carlo where he is speaking with reinsurers in a bid to convince them that Christchurch and New Zealand would not be overly risky to insure in future.