Transport Minister Steven Joyce says the cost of the Rena oil spill is approaching the $10 million mark.
While refraining from giving an exact figure, Mr Joyce says that about a week ago the cleanup cost was about $4 million.
He also says the recovery of containers from the ship, which is grounded on the Astrolabe reef in Bay of Plenty, is going to take a long time.
'Everybody should be prepared that that will be a significantly long haul," Mr Joyce says, "and given the fact that storms do occur from time to time [there] is every likelihood further containers will end up in the sea."
Pumping has stopped temporarily on the Rena, as salvors shift their focus from port to starboard.
Maritime New Zealand says the pump in the port No 5 tank, which held 772 tonnes, has now lost suction at a very low level, which spokesperson Kenny Crawford says is good news.
Mr Crawford says draining the flooded starboard passageway will allow access to a submerged tank that holds 358 tonnes of oil.
As of 5am Thursday, 808 tonnes of fuel oil had been pumped from the ship.
