The Treasury estimated the total financial cost of damage from the earthquake at between NZ$10 billion and NZ$15 billion - two to three times the estimated NZ$5 billion cost of an earlier earthquake that struck the city last September.

In addition, the wider economic impact of the earthquake, combined with already slower than forecast economic growth, could leave nominal GDP a cumulative NZ$15 billion lower over the next five years to 2015.

That is equivalent to about 1.5 per cent of the total value of GDP over this period, it said.

The Reserve Bank of New Zealand has held its key interest rate at 3.0 percent since September last year as the economy has struggled to pick up momentum and households and businesses cut spending. Unlike many other developed nations, the economy has shown few signs of gaining traction in recent months.

The latest death toll from the earthquake is 166, but is likely to rise above 200 as the search for survivors was officially called off on March 3, with buildings, roads, electricity and water infrastructure all severely damaged by the magnitude 6.3 quake.