GENEVA, March 26 (Reuters) - The head of the World Trade Organization said on Thursday the multilateral system has fundamentally changed and that countries must look to the future to consider how to reform the global trade system.

"The world order and multilateral system we used to know has irrevocably changed. We will not get it back...We must look to the future," WTO Director-General Ngozi Okonjo-Iweala told delegates at the opening of the 14th WTO ministerial conference in Yaounde, Cameroon.

While 72% of global trade still takes place under WTO rules, with growth in AI-related trade providing a bright spot, Okonjo-Iweala said the world trading system faces significant uncertainty due to the Middle East conflict and impact of U.S. tariffs on countries around the world.

Okonjo-Iweala set out a list of problems facing the WTO, including the paralysis of the WTO's dispute settlement body and transparency in notifying the use of subsidies.

Only 64 members had filed subsidy notifications at the WTO for 2025, meaning 102 had not, Okonjo-Iweala said.

"Lack of transparency leads to lack of trust, and that breeds suspicions of unfairness and anti-competitive behaviours," she told delegates. This contributed to a "vicious cycle" of mistrust which is holding back members from agreeing new rules and reforms, Okonjo-Iweala added.