The deal, which Beijing has not commented on, would be a major win for Boeing, which has lost ground to Airbus in one of the world’s largest aviation markets.

Beijing approved beef shipment licenses for hundreds of American slaughterhouses, although it appeared to claw back many of them later in the day.

A central question hanging over the summit this week is whether China will agree to extend a temporary postponement of even tougher rare-earth export controls.

The country’s exports surged and its trade surplus with the United States widened ahead of President Trump’s scheduled visit next week to Beijing.