The cost of cleaning up oil spilled from the container ship Rena has reached $3.5 million.
Revealing details on Sunday of the financial effects of the spill, Transport Minister Steven Joyce also said he had been unhappy with the response of the firm that chartered the vessel.
Mr Joyce told TVNZ's Q+A programme the total cost of the disaster will depend on what happens with the oil still aboard the stricken ship.
Some 350 tonnes of oil has leaked from the vessel since it grounded on Astrolabe Reef on 5 October, polluting the ocean and nearby Bay of Plenty beaches. More than 1300 tonnes of fuel remains on board.
While the final cost of the oil response could run into the tens of millions of dollars, Mr Joyce said, some of that would be met by insurers of the ship's owners Costamare.
The minister did not know what the cost of the salvage operation would be but said that, and the cost of dealing with the containers, would be up to the owners.
Charter company told to step up
Mr Joyce said he was not happy with the response last week of the Mediterranean Shipping Company, the world's second largest container shipping firm, which chartered the vessel.
He says the firm has shrugged off responsibility and he has called a meeting with its representatives for Monday morning.
"They have to step up and be part of this exercise," he said.
Mr Joyce defended early salvage efforts after the ship first hit Astrolabe Reef, saying salvage experts succeeded in containing oil aboard the ship, thus limiting the scale of the disaster.