Malaysian Prime Minister Najib Razak confirmed on Thursday that a Boeing 777 wing segment discovered in the Indian Ocean island of Reunion is from the missing Flight MH370, the first real breakthrough in the search for the plane that disappeared 17 months ago.

"Today, 515 days since the plane disappeared, it is with a heavy heart that I must tell you that an international team of experts have conclusively confirmed that the aircraft debris found on Reunion Island is indeed from MH370," Najib said in a televised statement.

Malaysia Airlines Flight MH370 disappeared in March last year enroute from Kuala Lumpur to Beijing with 239 passengers and crew on board.

Investigators in France ascertained that the barnacle-covered debris, a 2-2.5 meter (6.5-8 feet) wing surface known as a flaperon, belonged to MH370 just days after Malaysia identified it as being part of the same model, a Boeing 777.

The confirmation brings some closure to the relatives of those on board but does not shed any light on what happened to the airliner.

"I would like to assure all those affected by this tragedy that the government of Malaysia is committed to do everything within our means to find out the truth of what happened," Najib said.

The plane piece washed up last Wednesday on Reunion, a volcanic island of 850,000 people that is a full part of France, located in the Indian Ocean near Madagascar.

Reunion is roughly 3,700 km (2,300 miles) from the broad expanse of the southern Indian Ocean off Australia where search efforts have focused, but officials and experts said currents could have carried wreckage that way, thousands of kilometers from where the plane is thought to have crashed.

Malaysia Airlines said in a separate statement that the relatives of passengers and the crew had been informed.

The airline said the discovery was a major breakthrough in resolving the disappearance of MH370.

"We expect and hope that there would be more objects to be found which would be able to help resolve this mystery," it added.

The discovery of the flaperon led to a frantic search for more possible wreckage from the missing plane in the island.