Central banks have run out of firepower to fight the next economic downturn, according to global finance chiefs gathered at an investment forum in Saudi Arabia on Tuesday.

Billionaire hedge-fund founder Ray Dalio went further, saying the global economy is under threat from an explosive mix of ineffective monetary policy, a rise in the wealth gap and climate change.

The combination will lead to a “scary situation” over the next decade, according to Dalio, whose investment management firm, Bridgewater Associates, is the world’s biggest hedge fund.

“The technology and increasing use of artificial intelligence and increased productivity will also substantially increase the wealth gap, the job gap, the wealth and ideological conflicts within countries,” he said in Saudi Arabia, where he’s attending the Future Investment Initiative.