Boeing Co. is in advanced discussions with Beijing to supply as many as 500 commercial jets, people familiar with the matter told Bloomberg. The prospective multibillion-dollar order would be the U.S. manufacturer’s largest in China and could end an eight-year sales drought in the world’s second-largest aviation market. Negotiators are still working out the mix of aircraft types and delivery timetables, the sources said. Completion of the transaction depends on the United States and China reaching broader trade understandings, including the rollback of tit-for-tat tariffs that have curbed aircraft deliveries since 2019. Chinese economic planners have begun surveying domestic airlines on fleet requirements to prepare for the possible purchase. A deal of this scale would narrow Boeing’s gap with Airbus SE, which recently secured its own order of roughly 500 jets from Chinese carriers. Boeing has booked just 30 Chinese orders since 2019 after regulators there were the first to ground the 737 Max and escalating trade frictions further chilled demand. News of the talks lifted Boeing’s shares as much as 3.7% in U.S. pre-market trading and about 2% after the opening bell. The last major Chinese purchase of Boeing aircraft came during President Donald Trump’s state visit to Beijing in 2017, when carriers agreed to buy 300 jets valued at roughly $37 billion.