Transport Minister Gerry Brownlee expects to announce the outcome of negotiations with the owners of the Rena, in the next couple of weeks.
Maritime New Zealand says the cost of the clean-up since the ship went aground on the Astrolabe Reef off Tauranga last year could be $50 million.
As at February, about $39 million had been spent by Crown agencies.
Costamare Shipping is legally liable to pay $11.3 million of the environmental costs, property damage and loss of business income.
Mr Brownlee says discussions with the company are coming to an end but he won't speculate on what it might pay.