He said the Earthquake Commission disaster fund was depleted, but a Government guarantee would mean all insurance claims were met.
English said not only were South Island roads badly damaged, but also the ports at Picton and Wellington.
Key said the wild weather in Wellington was causing "yet another complicating factor to the aftermath of the earthquakes".
It was making travel difficult in Wellington and hampering efforts to airlift people out of Kaikoura, he said.
Read more: Bad weather in Wellington
Key said the Government's other priority was helping small businesses in Kaikoura, which had immediate and possibly medium-term needs.
He said "over time" State Highway 70 and possibly the southern end of SH 1 would open to allow traffic into the township.
"But there will be quite a disruption there for a period of time."
Civil Defence Minister Gerry Brownlee said the Government was also thinking about Kaikoura's long-term future.
It was largely dependent on a tourist market, he said, but also had fishing and farming interests.
Brownlee said the Government was looking at how to "maintain activity" in the region and support the residents "through what is a difficult time".
Work was also under way to consider the quake's impact on other North Canterbury towns, and on Wellington.
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