Top global banking chiefs have said they are concerned the financial sector’s next crisis may come from rising geopolitical uncertainty, as extreme events could test market resiliency, according to Reuters.

The trigger for the next global financial crisis is likely to come from the geopolitical or political space, said Morgan Stanley Chairman and CEO James Gorman.

“The challenges to democracy in some countries around the world are pretty evident,” Gorman said without elaborating.

Deutsche Bank CEO Christian Sewing said markets have largely been resilient in the face of global events but any calm is vulnerable to the risk of new events.