The U.S. and China are set to resume high-level trade negotiations and are scheduled to talk by phone next week, White House economic adviser Larry Kudlow said Wednesday. "They will be on the phone this coming week," Kudlow said, according to Bloomberg News . "And they will be scheduling face-to-face meetings. Lots of communications." Reuters reported the two sides were arranging a principal-level phone call next week; principal negotiators are U.S. Trade Representative Robert Lighthizer and China's Vice Premier Liu He. There have already been lower-level phone conversations this past week. Kudlow said face-to-face meetings would resume "soon," Reuters reported. The two sides have not met since early May, when an 11th round of talks stalled. On Saturday, President Donald Trump and China's President Xi Jinping announced a tariff truce as they aimed to restart trade negotiations.