Boeing executives and Chinese airline officials have reportedly finalized terms for a landmark 500-aircraft purchase of 737 Max models, marking one of Boeing’s largest potential sales. Parallel discussions cover a separate widebody agreement for about 100 Dreamliner and 777X jets, though that deal would be announced at a later date.

The firm order is expected to be unveiled during President Trump’s first state visit to China since 2017, scheduled for March 31 to April 2 in Beijing. The deal underscores how Boeing’s commercial interests are intertwined with U.S. diplomatic efforts, with President Xi Jinping slated to visit Washington later this year.

Boeing shares jumped as much as 4% following news of the pending order, making it the top performer on the Dow Jones Industrial Average during midday trading. Investors view the potential deal as a significant boost to Boeing’s order backlog and production pipeline.

Despite advanced talks, the agreement is not guaranteed, with potential delays from geopolitical tensions such as the war with Iran and U.S. export restrictions on aerospace technology. Negotiators are pushing for firm commitments rather than headline figures amid ongoing wrangling over engine and component exports critical to China’s aviation sector.