Maritime New Zealand is monitoring a small oil spill at the Raroa platform, about 70 kilometres off the Taranaki coastline.
The operator, OMV, says about 250 litres of oil was spilt on Friday when a pipe split during a routine transfer operation.
OMV was tracking the slick, which was about 10 kilometres from the platform yesterday, and had deployed a support vessel with a skimmer for collecting oil.
Maritime New Zealand said it was monitoring the situation.
It expected the oil to break up considerably and if it does hit the coast it would arrive as small tar balls, they said.