Maritime New Zealand (MNZ) said it was monitoring the situation of a small oil spill at the Raroa platform, about 70 kilometres off the Taranaki coastline.
The operator, the New Zealand branch of international oil company OMV, says about 250 litres of oil was spilt on Friday when a pipe split during a routine transfer operation. It says it sincerely regrets an oil spill that is being investigated by MNZ.
A flight with MNZ observers on board this morning couldn't find any signs of an oil sheen following the spill.
Peter Zeilinger, managing director of OMV New Zealand Ltd, which runs the operation, said a small spill occurred when oil from the Raroa was being transferred to the tanker Nectar.
"The transfer hose developed a leak close to the connection point on board the Nectar and oil spilled onto its deck," Zeilinger said.
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.
It expected the oil to break up considerably and if it does hit the coast it would arrive as small tar balls, they said.