Translate the following English sentence to French:
"A time came when it seemed that some progress had been made, though far from anything that could be considered satisfactory, but in the end even that slight progress has vanished in the last few days, since the US has petitioned the ICAO under Article 84 of the Chicago Convention against the European Union concerning the regulation whose purpose, as I said, is to protect the environment."
Puis il est apparu un jour qu' un petit progrès avait lieu, bien qu' il fût certes loin d' être tenu pour satisfaisant, mais ce petit progrès lui-même a tourné court puisque, ces jours-ci, la partie américaine, en vertu de l' article 84 de la Convention de Chicago, a intenté auprès de l' OACI une action contre l' Union européenne à cause de ce règlement qui, je l' ai dit, vise à protéger l' environnement.