The kiwi has been "remarkably resilient", although that's largely due to a weaker greenback and this week's fourth-quarter gross domestic product data - due Thursday - "will be the acid test to see if we [the kiwi] can continue" to gain, Slabbert said.
GDP is forecast to have expanded 0.8 per cent in the three months ended December 31 and 3.1 per cent from a year earlier, according to the median in a Bloomberg poll of 12 economists. The Reserve Bank projects quarterly growth of 0.7 in the fourth quarter.
The kiwi may have also benefited as some trade-war fears abated after US President Donald Trump offered exemptions to Canada, Mexico and Australia on planned steel and aluminium tariffs.
A spokesman for Trade and Export Growth Minister David Parker said New Zealand has formally sought an exemption from the tariffs, and while the details are still to be clarified, New Zealand may fall within the flexibility offered to close security partners. Prime Minister Jacinda Ardern also said ministers were working to get an exemption for New Zealand.
The kiwi rose to 78.05 yen from 77.70 yen on Friday in New York and traded at A93.06c from A92.64c. It lifted to 59.39 euro cents from 59.10 cents last week and increased to 52.81p from 52.52p. The local currency gained to 4.6333 Chinese yuan from 4.6052 yuan last week.
New Zealand's two-year swap rate rose 3 basis point to 2.22 per cent, and 10-year swap rate rose 4 basis points to 3.25 per cent.