U.S. trade talks with China ended Friday as Liu He, the top Chinese trade negotiator, left the Office of the U.S. Trade Representative.

div > div.group > p:first-child">

Treasury Secretary Steven Mnuchin called the discussions about a possible trade agreement "constructive." Both Mnuchin and U.S. Trade Representative Robert Lighthizer shook hands with Liu as he left the office.

Washington and Beijing engaged on Thursday and Friday as they tried to salvage a trade deal that appeared to be within their grasp only a week ago. The U.S. increased tariffs on $200 billion in Chinese goods to 25% from 10% on Friday following what it called China's decision to back out of key commitments to a developing agreement.

Investors have watched the talks closely. Major U.S. stock indexes dove on Friday after the duties went into effect and President Donald Trump said "there is absolutely no need to rush" to strike a deal.

The U.S. aims to address grievances including intellectual property theft, forced technology transfers and its trade deficits with Beijing.

This story is developing. Please check back for updates.

Subscribe to CNBC on YouTube.