 It was developed in response to a French air ministry specification of 1936 for a transatlantic airliner for Air France with a range of and capacity for 20 passengers and 500 kg of cargo.Designs were submitted by Latécoère, Lioré et Olivier and by Potez-CAMS as the Laté 631, LeO H.49 and the Potez-CAMS 161 respectively, and examples of all designs were approved for construction.A large mock-up, resting on simulated water, was displayed at the 1938 "Salon de l'Aéronautique".