Leaders of the world's biggest powers met Sunday to try to revive the sluggish world economy. The global economy is being threatened by rising protectionism and risks from highly leveraged financial markets, Chinese President Xi Jinping said at the open of a two-day summit of leaders from G20 nations. Deputy Crown Prince Muhammad Bin Salman, second deputy premier and minister of defense, is leading Saudi Arabia's delegation. With the summit taking place after Britain's vote in June to exit the European Union and before the US presidential election in November, observers expect G20 leaders to mount a defense of free trade and globalization and warn against isolationism. The global economy has arrived "at a crucial juncture," Xi said, in the face of sluggish demand, volatile financial markets and feeble trade and investment. "Growth drivers from the previous round of technological progress are gradually fading, while a new round of technological and industrial revolution has yet to gain momentum," he said. G20 countries are set to agree in a communique at the end of the summit that all policy measures — including monetary, fiscal and structural reforms — should be used to achieve solid and sustainable economic growth, Japanese Deputy Chief Cabinet Secretary Koichi Hagiuda said. "Commitment will be made to utilizing all three policy tools of monetary and fiscal policies and structural reforms to achieve solid, sustainable, balanced and inclusive growth," Hagiuda told reporters on the sidelines of the summit. Xi also called on G20 countries to match their words with actions. "We should turn the G20 group into an action team, instead of a talk shop," he said. The G20 brings together representatives of 85 percent of the world's GDP and two-thirds of its population. The summit was preceded by a flurry of diplomatic activity on issues ranging from climate change and the war in Syria to international trade. — Agencies