Trade talks with China 'made headway', says US envoy

US-Chinese talks on a war of wills over Beijing's technology ambitions have "made headway" on important issues, the chief American envoy said, but he gave no indication whether Washington would postpone a looming tariff hike.

Robert Lighthizer expressed optimism but gave no details of the two days of negotiations. Economists said they were too brief to resolve the tariff fight that threatens to chill weakening global economic growth.