A piece of airline debris that washed up on the remote Indian Ocean island of Ré union was to be sent to France on Friday, but authorities there cautioned it would be at least days before investigators come to any conclusion about whether it is part of Malaysia Airlines Flight 370.

An Australian official suggested the plane part discovered on the French overseas territory off the eastern coast of Africa was "very likely" from a Boeing 777, the same model as the jetliner that went missing nearly 17 months ago.

French authorities are preparing for a more thorough technical assessment once the wreckage is brought to the southwestern French city of Toulouse this weekend. French television showed images of the aircraft piece wrapped and sealed and ready to board an aircraft.

The debris is due to leave on Friday evening, a spokeswoman for the Paris prosecutor's office said. It will then be several days before an expert can start an assessment.

The discovery of the aircraft part on French soil puts France in a leading role, but its active involvement adds another layer of complication to what has already been a multi-jurisdictional probe.

Efforts to ascertain what happened to Flight 370 have at times been hobbled by multinational authorities that slowed responses. Malaysia leads the crash probe and Australia has been directing the search for wreckage taking place in a 23,200-square-mile area off the country's western coast.

China meanwhile, has put pressure on Malaysia for progress on the probe after early missteps. Two thirds of the victims were Chinese.

The flight is believed to have crashed in the Indian Ocean on March 8, 2014 after veering sharply off its intended flight path from Kuala Lumpur to Beijing with 239 people onboard.

If a link is established with the aircraft debris, which measures about 10 feet by 5 feet, it would be the first piece of the plane to be recovered in what has been modern aviation's greatest mystery.

Martin Dolan, chief commissioner of Australia's Air Transport Safety Bureau, said Friday that the winged fragment appears to come from a 777 aircraft, "and if it is from a 777 aircraft, then it is from MH370."

"We are not saying we're 100% certain at this stage. But we are assuming at this stage that it is very likely," he said.

French judicial authorities had already opened an investigation due to the presence of four French nationals on board the Malaysia Airlines flight. But that probe didn't go very far.

Paris prosecutor Franç ois Molins has appointed an investigative magistrate to lead the new probe into what appears to be a flaperon control surface. If the item is connected to Flight 370 it could then be transferred to Malaysian authorities, the prosecutor's spokeswoman said. "We're not there yet," she said.

France's defense ministry said the wreckage would be transferred to an aeronautical test center at Balma, near Toulouse, which has assisted other plane probes. The item has remained at Ré union airport for the past couple of days under strict surveillance.

The French expert appointed to examine the wing fragment won't start working on the debris before next Wednesday, the prosecutor's spokeswoman said.

The magistrate would have to formally ask the BEA, France's air accident investigation office, for assistance, an official close to the process said. Malaysian officials are expected to participate in the examination and the U.S. National Transportation Safety Board also may play a role.

Elaine Chew, whose husband Tan Size Hiang was a cabin crew member on the flight, said investigators must very carefully conduct their probe.

"One part of me hopes that this is it," she said. "Finding the debris will finally bring some closure."

If the aircraft part is identified as coming from Flight 370, Australia's Deputy Prime Minister Truss said it may lead authorities to widen the search around Ré union and nearby Madagascar for other wreckage. "But that will be a matter for the French authorities and some of the African countries because that will be their search zone and would be their responsibility."

Australian officials have previously said the search would be called off if the plane isn't found within the current search zone or if no further evidence comes to light.

Celine Fernandez contributed to this article.

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