Air France-KLM's board of directors has appointed Benjamin Smith as its new CEO.

Prior to his appointment to the top job at Air France-KLM, Smith served as the President and COO of Air Canada.

Major French trade union issued a joint statement condemning the appointment.

The major trade unions representing Air France KLM staff issued a joint statement on Thursday to protest the appointment of Air Canada President and COO Benjamin Smith as Air France-KLM's new chief executive.

"Concerning the choice of new chief executive...the trade unions would like to state that it's inconceivable that the company Air France - which has been French since 1933 - would fall into the hands of a foreign director," the unions said in the statement.

Air France-KLM's board met on Aug. 16 to approve Smith's nomination as the company's next CEO.

"The arrival of Benjamin Smith is excellent news for the Group," Air France-KLM non-executive chairman Anne-Marie Couderc said in a statement. "Benjamin is a world-renowned leader in the airline sector who successfully transformed Air Canada."

An Air France Airbus A380. Flickr/Maarten Visser Smith's appointment fills a major management void after former CEO Jean-Marc Janaillac quit in May when staff rejected his offer of a pay deal aimed at ending a wave of strikes that have so far cost the company 335 million euros ($381 million).

Known to speak French, Smith has a track record in dealing with unions and was the main negotiator in talks with pilot and cabin crew staff at Air Canada that resulted in a 10-year agreement in 2015.

The French state has a 14 percent stake in Air France-KLM, while Delta Airlines and China Eastern Airlines each hold 8.8 percent.

Government officials say President Emmanuel Macron is open to a non-French national leading the group for the first time.

Smith is expected to take up his new position no later than September 30.