UPDATE 3.15PM: The sunken stern section of the Rena has moved position on Astrolabe Reef.

Spokesperson for the owners and insurers Hugo Shanahan says divers preparing to cut the sunken accommodation block have observed the position of the stern on the reef has changed.

A visual of the Rena stern's previous position on Astrolabe Reef.

He says the stern was previously surveyed listing at 55 degrees, and that list to starboard has now increased.

Hugo could not confirm the extent the list has increased but says a dive survey to be undertaken in the next few days will confirm this.

'From the visual inspection from the divers, it looks like the list has increased – you really need to conduct this survey to get the exact detail, but from what they have seen there it looks as though it has changed position on the reef.

'Divers will spend the two working days conducting a visual survey to confirm the changes in the ship's position,” says Hugo.

Hugo says divers have not seen any damage to the reef itself from the movement.

The change in position was spotted by divers on Wednesday afternoon and the movement is believed to have occurred sometime after Cyclone Lusi hit the region at the weekend.

'They were down there preparing for the second cut and lift and that's when they saw the list had changed.”

'It is likely to have occurred after the completion of that first cutting action, and Lusi coming through NZ.”

Hugo says a full wreck survey will be conducted on the Rena following removal of the first half the accommodation block.

The owner and insurer have also commissioned an ADUS (underwater sonar) survey to secure a 3D computer model of the ship's position, and confirm the extent of the movement and any effect this may have had on the structure. The remaining bow section will also be surveyed.

'We will be able to compare that to a previous survey.”

Captain John Owen of The Swedish Club, the owner's insurer says the survey will help clarify what impact this movement might have on future salvage operations and any updates necessary to the assessment information of the resource consent application.

'We're sharing this information now so that the community knows what is happening on site. And to confirm that there will be further delays to our work programme,” says the captain.

'A further update will be provided once the survey has been completed and the information thoroughly assessed, which should be by the end of April.”

Captain Owen says since a baseline survey was last carried out on the ship's position in April 2012, they have been consistently monitoring the ship for movement and none has been detected until now.

Hugo says this movement will delay the next phase of cutting the accommodation block.