The Reserve Bank has cut its benchmark interest rate by three quarters of a percentage point, to support the economy against the impact of the Covid-19 virus.

The central bank cut its official cash rate to a record low 0.25 per cent from 1 per cent.

Reserve Bank governor Adrian Orr says the cut is necessary to support businesses and employment.

The Official Cash Rate of 0.25 per cent, will remain at this level for at least the next 12 months.

The negative economic implications of the COVID-19 virus continue to rise warranting further monetary stimulus, says a statement on the Reserve Bank website.

"Since the outbreak of the virus, global trade, travel, and business and consumer spending have been curtailed significantly. Increasingly, governments internationally have imposed a variety of restraints on people movement within and across national borders in order to mitigate the virus transmission.

"Financial market pricing has responded to these events with declining global equity prices and increased interest rate spreads on traditionally riskier asset classes."

The negative impact on the New Zealand economy is, and will continue to be, significant, says the Reserve Bank.

"Demand for New Zealand's goods and services will be constrained, as will domestic production. Spending and investment will be subdued for an extended period while the responses to the COVID-19 virus evolve.

"Several factors will continue to assist and support economic activity in New Zealand.

"New Zealand's financial system remains sound and our major financial institutions are well capitalised and liquid. The Reserve Bank is also ensuring that the banking system continues to function normally.

"The Government is operating an expansionary fiscal policy and has imminent intentions to increase its support with a fiscal package to provide both targeted and broad-based economic stimulus.

"The New Zealand dollar exchange rate has also depreciated against our trading partners acting as a partial buffer for export earnings.

"And, the Monetary Policy Committee agreed to provide further support with the OCR now at 0.25 percent. The Committee agreed unanimously to keep the OCR at this level for at least 12 months.

"The Committee also agreed that should further stimulus be required, a Large Scale Asset Purchase programme of New Zealand government bonds would be preferable to further OCR reductions."

Last week, the bank outlined a range of unconventional monetary policy tools such as negative interest rates, special loans to banks, and buying bonds to put money into the economy.

The last time the Reserve Bank made such a big cut was in March 2011 after the Canterbury earthquake.

- Additional reporting by RNZ