Work is set to begin on Friday to remove the three shipping containers which came off the HMNZS Manawanui when it sank off Samoa's coast earlier this month.

In a statement, the New Zealand Defence Force (NZDF) confirmed it is working with a local contractor, ARK Marine, to remove the containers from the reef off the southwest coast of Upolu.

Once work begins, it is expected to take at least three days — weather permitting — to remove all three containers.

The process of removing the 10ft containers involves floating them and then towing them to shore. The NZDF said preparation is underway by the contractor, which includes getting rigging gear ready.

"The containers are not watertight and have sustained some structural damage, and are being moved by tides and swell," the NZDF said.

It said Samoan Government officials have been involved throughout the process and have approved the removal plan.

NZDF senior national representative commodore Andrew Brown said this is "still a complex operation".

"We have carefully considered a number of options for removing the containers. Especially, we are working hard to minimise the impact on the marine environment," he said.

"Other considerations include the prevailing weather, weight of the containers, and potential biosecurity risks.

"While it is expected it will take three days for the removal of the containers, it may be that weather and sea conditions, or other considerations, mean that the timetable is not met.

"However, we are hopeful that the conditions will be such that all containers will be removed from the reef over coming days."

Earlier today, the HMNZS Canterbury arrived in Apia's harbour to support the Government of Samoa's hosting of the Commonwealth Heads of Government Meeting.

The ship is also transporting equipment that can assist in the NZDF's ongoing response.

The NZDF task group ashore and Maritime NZ have confirmed so far no pollution has been found on the shorelines, nor any deceased wildlife.

Uncrewed RNZAF aerial vehicles have also been assisting with shoreline surveys, along with a RNZAF P-8A Poseidon and crew which have conducted several surveillance flights to provide imagery and assessments of the site.

In an update at the time, Brown said he is headed to the south east coast of Upolu to attend a community engagement meeting with residents of the Safata District, who have been "the most impacted" by the ship's sinking.

He added the meeting, organised by Samoan government officials, is a "very important opportunity" to hear first-hand from the people of the villages.

"We might not have all the answers today, but as I've said before, we are committed to working with the Samoan government to carefully consider and plan the next steps, today, myself and the High Commissioner are here to listen."