The Reserve Bank of New Zealand (RBNZ) is expected to signal a "data-dependent easing bias" in its policy outlook, leaving the option of pausing its cutting spree beyond April, Westpac's chief economist wrote in a Thursday note.

The market expects the RBNZ to slash the key rate by 25 basis points to 3.5% at its April 9 meeting, a move widely signaled by policy-setters in their previous communication.

But Westpac chief economist Kelly Eckhold said a rate cut this month is "likely the wrong thing to do" and that the Reserve Bank should instead leave the official cash rate (OCR) unchanged next week and consider a cut in May.

"An evaluation of the data flow in recent months shows both an improving economy and robust inflation. Given the mandate is solely focused on inflation it's hard to make the case for cutting rates at every meeting from here," Eckhold said.

The analyst expects the RBNZ to signal that another rate cut in May "is more likely than not" but that cuts after that are "more speculative than indicated at the February Monetary Policy Statement."

Eckhold cited global uncertainties and the perception the OCR is above the neutral rate as the main drivers of the bank's the easing bias.