Brazil's Gol Linhas Aereas Inteligentes, the country's biggest domestic airline, said it will be the first to resume commercial flights using Boeing's 737 Max after regulators lifted a 20-month ban on the embattled aircraft. Passenger operations on the Max will start from Wednesday on domestic routes to and from its Sao Paulo hub, Gol said in a statement, without specifying which destinations the Max will serve. "Over the past 20 months, we have watched the most comprehensive safety review in the history of commercial aviation unfold, bringing together regulatory agencies and airlines from around the world to monitor and contribute to the upgrades in aircraft systems and pilot training," said Celso Ferrer, vice-president of operations at Gol. Following the aircraft's new certification by the US Federal Aviation Administration and Brazil's National Agency Civil Aviation Administration, Gol is "fully confident" in the Max's return to service, Mr Ferrer, who is also a commercial pilot and trained to fly the 737 Max, said. The airline trained 140 of its pilots in the US using a Max simulator, meeting all the technical and operational requirements outlined in the plan approved by the US and Brazilian regulators, and completed a series of technical flights. Gol, Brazil's sole operator of the 737 Max, said all seven of the 737 Max aircraft in its current fleet should be cleared to return fully to operation by the end of December. It will gradually reincorporate the jets into its flight schedules according to operational needs. Gol's announcement comes after American Airlines said it will re-launch its Max service on flights connecting Miami with New York by the end of 2020. Boeing's best-selling jet was grounded in March 2019 after two crashes within five months of each other collectively killed 346 people. Boeing redesigned the flight-control software following the incidents.