The deaths of three Canadians killed when the light plane crashed in Antarctica have been confirmed.

The plane, returning from the South Pole, crashed on an icy slope near the summit of Mt Elizabeth on Wednesday.

Poor weather conditions meant the wreckage was not sighted until Saturday.

Antarctica New Zealand operations and infrastructure manager Graeme Ayres said on Sunday the three men's deaths had been confirmed.

Southern Lakes Helicopters, contracted to the organisation, were working along side their United Stated counterparts, PHI Inc pilots, to recover the bodies, he said.

Mr Ayres extended Antarctica NZ's deepest sympathies to the families of the Kenn Borek Air Twin Otter crew.

"We remained hopeful throughout the search process that the vastly experienced crew would have survived... We are so sad our optimism alone was not sufficient to provide the outcome for which we all hoped."

The wreckage is located about 3900m up the 4480m mountain and the recovery of the men's bodies is weather dependant.

"We recognise the tremendous efforts of our United States and New Zealand teams, who are working in difficult and at times, extreme conditions," Mr Ayers said.

"The families by now will know these teams are doing all they can to return their loved one to them."

Canadian media has identified the men killed as experienced pilot Bob Heath, of Calgary-based Kenn Borek Air, Calgarian Mike Denton and Perry Andersen of Collingwood.

The intention is to return the men's bodies to New Zealand and then repatriate them to Canada.

The Twin Otter was operated by a Canadian company and officials in Canada are investigating the crash.