The International Monetary Fund has welcomed the start of a "constructive dialogue" between US President Donald Trump and Chinese President Xi Jinping, calling the meeting an opportunity to ease trade tensions and uncertainty between the world's two largest economies, saying it is important for global growth.

IMF spokeswoman Julie Kozak said at a press conference that it is "very important" that the world's two largest economies speak at the highest level, commenting on the first results of the Trump-Xi summit in Beijing.

"We welcome the fact that there is a constructive dialogue between the two countries. Anything that contributes to reducing tensions and trade uncertainty is good for both major economies, but also for the global economy," Kozak said.