Chinese President Xi Jinping said downward risks and uncertainties for the global economy are on the rise, and pledged to boost the power of emerging markets on the world stage.

The external environment for developing economies is complicated and grim, Xi said in a speech Tuesday to the BRICS summit of leaders from Brazil, Russia, India, China and South Africa in the coastal city of Xiamen. Xi reiterated that China opposes protectionism and firmly supports the multilateral trading system.

“Beggar-thy-neighbor policy and a zero-sum game mindset don’t benefit global economic growth,” Xi said, echoing a theme he has sounded this year, including at the World Economic Forum in Davos. The remarks came a day after he met with Mexican President Enrique Pena Nieto, who also attended the summit, and the two pledged to defend free trade.

Xi added that China will provide $500 million to ease hunger and poverty in other emerging economies and called for developed nations to beef up support for developing countries.

While Xi has spoken against protectionism, officials from the U.S. have criticized China’s trade practices and market access, and the White House recently stepped up pressure over perceived intellectual-property abuses.