The threat was being assessed after the magnitude 7.5 quake this afternoon.
"Based on current information, the initial assessment is that the earthquake is unlikely to have caused a tsunami that will pose a threat to New Zealand," New Zealand Civil Defence said at 3.25pm.
The tremor was located in the Drake Passage, a body of water located between the southern tip of South America and Antarctica, the United States Geological Survey said.
The quake had a depth of 10.8km. It struck at 2.16pm (NZ time) and was initially reported by the USGS as being magnitude 8.0, before being downgraded.
Chile's Navy Hydrographic and Oceanographic Service issued a tsunami precaution for the Chilean Antarctic territory.
The USGS said there was no tsunami warning or threat, while Australia's Bureau of Meteorology had ruled out a threat to Australia.
Meanwhile, a 5.6-magnitude quake struck near the Myanmar-India border this afternoon, the European Mediterranean Seismological Centre said.
That quake was at a depth of 10km, it said.
- Reuters/Allied Media
