Kuala Lumpur:  Confirmation that plane debris washed up on a remote Indian Ocean island is from missing Malaysia Airlines flight MH370 appears imminent — representing the first breakthrough in one of the world's most baffling aviation mysteries.

A team from aircraft maker Boeing has been dispatched to France to confirm that barnacle-encrusted debris is from the plane that disappeared in March last year with 239 people on board.

Sources close to Boeing have been quoted in the United States as saying the company believes the two-metre-long wing part known as a flaperon​ is from MH370, but company experts will confirm it when they arrive at the offices of France's crash investigation agency laboratory in Toulouse over the weekend.

The debris washed up on the French island of Reunion, east of Madagascar, last Wednesday.

Malaysia Airlines told the Malaysian government on Friday that the wreckage was definitely from a Boeing 777, the same model of aircraft as flight MH370, citing an identification number.

"This could be the convincing evidence that MH370 went down in the Indian Ocean,"  Malaysia's Deputy Transport Minister Abdul Aziz Kaprawi​ said.

Malaysia has also sent officials to France to inspect the debris, saying the crucial identification will come through checking serial numbers on the wing part.

Malaysia says its remains responsible overall for the investigation into the disappearance of the plane while en route from Kuala Lumpur to Beijing while other agencies from France, the US and Australia are also contributing.

"There should be a metal plate attached to the flaperon close to where the number 657BB was printed," said Mohamed Suffian from the Malaysian Institute of Aviation Technology Research Innovation, referring to a number photographed on the wreckage.

"On the plate there should be the part's manufacturing date and batch number," he said, adding that Boeing would have recorded the batch number when the flaperon was attached to the plane.

The Toulouse laboratory, which employs 600 staff, will conduct tests to try to establish how the wing-flap came to be separated from the rest of the plane.

The same laboratory analysed pieces of debris from Air France flight AF447 that crashed between Rio de Janerio and Paris in 2009.

In January, Malaysia Airlines declared the plane's disappearance an accident, clearing the way for it to pay compensation to victims' relatives while a search for the plane continued in a vast area of the Indian Ocean west of Australia.

But an interim report of the investigation released in March deepened the mystery, raising serious doubts over whether the pilots or any of the crew hijacked the plane.

The possibility that one the pilots or crew diverted the plane thousands of kilometres off course before crashing into the Indian Ocean has been one of the most plausible theories about what happened.

The report said there were "no behavioural signs of social isolation, change in interests or habits, self-neglect ...  or alcohol abuse of the captian, first officer and the cabin crew".

Lawyers say confirmation the debris is from MH370 is expected to trigger a wave of new lawsuits against Malaysia Airlines.

With agencies