FILE PHOTO: U.S. Trade Representative Robert Lighthizer testifies before a Senate Finance Committee hearing on "The President's 2019 Trade Policy Agenda and the United States-Mexico-Canada Agreement" on Capitol Hill in Washington, U.S., June 18, 2019. REUTERS/Leah Millis/File Photo

WASHINGTON (Reuters) - As a tense meeting with top advisers on China trade talks ended, President Donald Trump turned to trade adviser Robert Lighthizer and told him to call China to warn that new tariffs were coming, two people familiar with the matter said on Friday.

The request to Lighthizer on Thursday came after Trump abruptly decided to threaten to raise tariffs by 10 percent on another $300 billion in Chinese exports to the United States, after U.S.-Chinese trade talks in Shanghai failed to lead to progress.

Trump was frustrated by the failure to advance the trade agenda during the Shanghai talks, and had gathered his top advisers in the Oval Office to discuss how to proceed.

The sources, who asked to remain unidentified, said Trump asked Lighthizer to call Chinese trade envoy Liu He and give him a heads-up that the tariff announcement would be made.

Since it was around 1 a.m. in Beijing at the time, Lighthizer said it might be hard to get him on the phone, the sources said.

“If you can’t reach him, just leave a message,” Trump told him, according to one source.

Moments later, Trump announced his tariff decision via a series of tweets that rocked markets.