A member of the U.S. delegation said the two sides would resume talks on Wednesday as they continue their first face-to-face meetings since Trump and Chinese President Xi Jinping agreed to a tariff truce during a meeting in Argentina on December 1.
The two governments have announced no details, but Asian stock markets rose on news the negotiations that originally were planned for two days were extended. The S&P 500 Index has fallen about 8% since Trump and Chinese President Xi Jinping agreed on a 90-day truce at a December 1 meeting in Argentina.
China and the United States have in the past repeatedly traded barbs over what Washington says is Beijing's militarization of the South China Sea by building military installations on artificial islands and reefs.
The China Daily said in an editorial that Beijing's stance remains firm that the dispute harms both countries and disrupts the global trade order and supply chains.
The US delegation, led by deputy trade representative Jeffrey Gerrish, had been scheduled to end its visit on Tuesday.
The U.S. did not send its top trade negotiators that have participated in previous U.S.
People familiar with the talks said the world's two largest economies were further apart on Chinese structural reforms that the Trump administration is demanding in order to stop alleged theft and forced transfer of USA technology and on how to hold Beijing to its promises.
Should China reform its regulation policies to allow more USA access to its markets, US negotiators want guarantees that they won't erase newfound openness by using government authority to block American companies.
The mid-level talks were the first face-to-face meeting between the two sides since both presidents met on December 1.
Delegates to the talks have not yet revealed what specifically was discussed, or if anything was agreed to.
Trump has imposed tariffs to pressure Beijing to change its practices on issues ranging from corporate espionage to market access and industrial subsidies.
Fears of a global slowdown and weaker corporate earnings - exacerbated by billions of dollars in tit-for-tat tariffs between the United States and China - have led to a sharp pullback on markets over the last few months.
"These issues are much more hard to solve immediately but are, frankly, much more compelling to US companies", said Jake Parker, vice president for China operations of the US-China Business Council, which represents American companies that do business with China.
Auto and property sales have slumped as Chinese growth fell to a post-global crisis low of 6.5 percent in the quarter ending in September.
The United States has long complained about access to the vast Chinese market and Beijing's demands US companies reveal their technology advances.
The US economy grew at an annual rate of 3.4 percent in the third quarter but surveys show consumer confidence weakening.
For their part, Chinese officials are unhappy with USA curbs on exports of "dual use" technology with possible military applications.