The black boxes from the Ethiopian Airlines plane that crashed on Sunday have been sent to France for analysis.

The decision not to send them to the US could be seen as a snub, as the plane, a Boeing 737 Max 8, was manufactured by an American company.

Ethiopian Airlines' director of public relations said that sending the data recorders to Europe and not the US was a strategic decision for the airline and the Ethiopian government, Bloomberg reported.

The US initially hesitated to ground the 737 Max, even as the European Union and several countries banned the planes from their airspace. The US on Wednesday reversed its decision.

Ethiopia sent the black boxes from the crashed Ethiopian Airlines plane to France in what could be seen as a snub to the US.

An official from the French aviation-investigation authority, BEA, told The Associated Press on Thursday morning that the flight-data recorder and the cockpit voice recorder had arrived in France for analysis. The official did not say how long that analysis might take.

Investigators are trying to find out why the four-month-old Boeing 737 Max 8 aircraft crashed shortly after taking off from Addis Ababa, the Ethiopian capital, on Sunday, killing all 157 people on board.

The decision to send the so-called black boxes to France is unusual, as France and other European countries typically deal with investigations into incidents involving European plane manufacturers, such as Airbus.

Asrat Begashaw, Ethiopian Airlines' director of public relations, said that sending the data recorders to Europe and not the US was a strategic decision for the airline and the Ethiopian government, Bloomberg reported.

People walking past a part of the wreckage. REUTERS/Tiksa Negeri

Bloomberg described the decision as a sign that authorities in the US "aren't trusted to determine the cause of the disaster after ruling that the model is safe to fly."

Read more: Boeing's CEO reportedly asked Trump not to ground the company's plane that has crashed twice in 5 months

The AP said that the BEA "has experience with global air crashes, and its expertise is often sought whenever an Airbus plane crashes because the manufacturer is based in France."

According to the BEA's website, the last time the authority investigated an incident involving a Boeing 737 plane was in 2013, and it last investigated an incident involving a Boeing plane, a Boeing 777, in 2017.

The headquarters of France's BEA aviation-investigation agency in Le Bourget. REUTERS/Philippe Wojazer

Reuters reported that US and Ethiopian aviation-safety officials discussed on Tuesday whether the data recorders "would go to Washington or London for download and analysis."

The US has a subordiante role in the investigation. The US National Transportation Safety Board said on Thursday that is dispatching three investigators to France to assist with analysis. It said they are "being assisted by technical advisers from the Federal Aviation Administration, Boeing and GE/Safran, the manufacturer of the engines."

Ethiopia announced that it would send the data recorders to Europe as the US Federal Aviation Administration continued to express confidence in the 737 Max, even as several countries around the world banned the planes from their airspace. After initially holding out on grounding the planes, the US reversed its decision on Wednesday.

Read more: Trump announces all Boeing 737 Max jets are immediately grounded following its 2nd crash in 5 months

The Boeing 737 Max fleet. Boeing

The Ethiopian Airlines plane was the second Boeing 737 Max 8 airliner involved in a fatal crash in five months. In October, Lion Air Flight 610 crashed in the Java Sea shortly after taking off from Jakarta, Indonesia, killing all 189 people on board.

Investigations into both crashes are ongoing. Boeing said on Tuesday that it would update 737 Max software that may cause the plane's nose to turn down.

The FAA said on Wednesday that similarities in the crashes "warrant further investigation of the possibility of a shared cause for the two incidents that needs to be better understood and addressed."