Emergency responders are preparing to resume pumping oil out of the grounded container ship Rena.

About 10 tonnes of oil was transferred off Rena onto the Awanuia on Sunday night before the operation was called off for safety reasons.

The Awanuia is back alongside the ship which ran aground on the Astrolabe Reef last Wednesday.

The Awanuia alongside the shipwrecked Rena.

The salvage team is transferring oil from Rena's forward port tanks to the rear of the vessel where it can be pumped off.

Work is continuing to pump fuel from the other forward tanks to the rear of the vessel, where it is easier and safer to take off the vessel.

The salvage team of 25 experts is onboard the vessel and they predict it will take two full days to transfer all of the oil out of the Rena's fuel tanks and onto barges.

This operation is weather dependent.

There is 1700 tonnes of oil and 200 tonnes of diesel the team is attempting to transfer off the ship.

There is about 100 tonnes of oil leaked into the duct keel and this cannot be pumped clear of the vessel.

Oil is leaking intermittently from the ship and into a slick which is now reaching shore with fuel oil today washing up on Mount Maunganui Main Beach.