The increased likelihood of a cut has analysts picking that any upward move would not be seen until at least 2021.
The New Zealand dollar plunged 1.4% following the 2pm announcement, falling from US69.1c to US68.1c.
ASB chief economist Nick Tuffley said the Reserve Bank had made a clear shift to flagging an OCR cut was now a possibility
''A key uncertainty [to a cut] is whether 2019 growth will pick up after a patchy 2018,'' he said.
Reserve Bank governor Adrian Orr said given the weaker global economic outlook and reduced momentum in domestic spending, the more likely direction of the next OCR move was down.
The global economic outlook had continued to weaken, in particular among some of New Zealand's key trading partners including Australia, Europe, and China.
''This weaker outlook has prompted central banks to ease their expected monetary policy stances, placing upward pressure on the New Zealand
dollar,'' Mr Orr said.
He said New Zealand employment was near its maximum sustainable level.
''However, core consumer price inflation remains below our 2% target mid-point, necessitating continued supportive monetary policy,'' he said.
Mr Tuffley said the Reserve Bank had noted the softer stance of other central banks lately, which had pushed up the strength of the New Zealand dollar.
''Our central view is still that the Reserve Bank can wait and gauge the economy's momentum for 2019. But an OCR cut is that much closer,'' he said in a statement.
Westpac chief economist Dominick Stephens said the Reserve Bank's stance
to suggesting a cut to the OCR was ''very different'' to February when it had said the next move could be ''up or down'' and that there were ''both upside and downside risks''.
''It is difficult to discern exactly how serious the Reserve Bank is about cutting the OCR,'' he said.
''We were very surprised by this change of stance because the economic situation has not changed much since the Reserve Bank's last missive in February.
''Perhaps the main reason for the change of stance was the actions of other central banks,'' Mr Stephens said.
Mr Orr said he expected ongoing low interest rates and increased government spending and investment to support economic growth during 2019.
''Low interest rates, and continued employment growth, should support household spending and business investment,'' he said.
Government spending on infrastructure, housing, and transfer payments also supported domestic demand, he said.
