Australia said on Thursday that plane debris recovered earlier this month from Mozambique was highly likely to have come from Malaysia Airlines Flight MH370, which was carrying 239 people when it went missing more than two years ago.

A Malaysian government investigation team has found that both pieces of debris are consistent with panels from a Malaysia Airlines Boeing 777 aircraft, said Australia's minister for infrastructure and transport, Darren Chester.

"The analysis has concluded the debris is almost certainly from MH370," he said. "That such debris has been found on the east coast of Africa is consistent with drift modelling ... and further affirms our search efforts in the southern Indian Ocean," Chester said.

Flight MH370 disappeared with 239 passengers and crew on board shortly after taking off from Kuala Lumpur bound for Beijing in March 2014.

A white, metre-long chunk of metal was found off the coast of Mozambique this month by a U.S. adventurer who has been carrying out an independent search for flight MH370. It arrived in Australia for testing earlier this week.

The debris was examined by investigators from Australia and Malaysia, as well as specialists from Boeing, Geoscience Australia and the Australian National University in Canberra.

Malaysia said this week it would send a team to retrieve a piece of debris found along the southern coast of South Africa to check whether it could also belong to MH370. 

The jet is believed to have crashed in the Indian Ocean and an initial search of a 60,000 square km has been doubled.

A piece of the plane's wing washed up on the French Indian Ocean island of Reunion, on the other side of Madagascar, in July 2015. So far only that piece, known as a flaperon, has been confirmed to belong to the missing plane.

What investigators really need to find is the main underwater wreckage, which would hold the plane's coveted flight data recorders, or black boxes. The data recorder should reveal details related to the plane's controls, including whether aircraft systems that might have helped track the plane were deliberately turned off, as some investigators believe.

But prospects for finding the debris field are running thin: Crews have already covered more than 70 per cent of the search zone, and expect to complete their sweep of the area by the end of June. No trace of the underwater wreckage has been found.

With files from The Associated Press