U.S. President Donald Trump called China's Xi Jinping tough and "extremely hard to make a deal with" on Wednesday, exposing frictions after the White House raised expectations for a long-awaited phone call between the two leaders this week.

President Donald Trump said in a late-night social media post that Chinese leader Xi Jinping was very tough to make a deal with, raising questions about whether a fragile economic truce between the world’s two largest economies will hold.