The company, which ordered 50 of the longer-range aircraft in 2019, plans to initially use this first plane on U.S. transcontinental routes later this year.

Even after the appeals court reaches a decision, the case is likely to end up in front of the U.S. Supreme Court and its 6-3 majority of conservative justices.

French Prime Minister François Bayrou decried the pact as "a dark day" for Europe.