SINGAPORE—After the U.S. and China reached an agreement this past week to end the latest skirmish in their trade war, President Trump wrote on social media that he and Xi Jinping will “work closely together to open up China to American Trade.

If a handshake agreement holds, it will merely undo some of the damage from the trade war that President Trump started.

United States and Chinese officials said they had agreed on a framework for a trade truce, which removed China's export restrictions on rare earths.