Prime Minister John Key says the United States has offered two helicopters to the New Zealand Defence Force to help evacuate people from quake-hit Kaikoura.

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The choppers are from the destroyer USS Sampson, which is in New Zealand for the Royal New Zealand Navy's 75th anniversary.

Key told reporters at Parliament this morning the top priority was getting 140 remaining people out of Kaikoura, which has been cut off by landslips.

About 1200 people were trapped in Kaikoura after the quake, and 600 of them had been sheltering at a Civil Defence centre.

Four New Zealand Defence Force NH90 helicopters have been carrying them out, 12 at a time.

The Malaysia Air Force has also offered a helicopter to assist with evacuations, Key said.

"So in terms of aerial support to get people out and to make sure that we get the provisions that are required in, we've got plenty of capacity now."

Japan will be sending a P-1 maritime surveillance aircraft.

Finance Minister Bill English reiterated Key's estimate that the cost of quake repairs would be in the "billions".

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.

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.

- NZ Herald