(Bloomberg) -- Singaporean Prime Minister Lee Hsien Loong warned that Southeast Asian nations may one day have to choose between the U.S. and China, as concerns deepen about a Cold War-style conflict between the world’s biggest economies.

“The circumstances may come where Asean will have to choose one or the other,” Lee said on Thursday night at the close of a regional summit hosted by the 10-member Association of Southeast Asian Nations. “I hope it does not happen soon.”

Lee’s remarks reflect fears among smaller nations that the U.S.-China trade war could disrupt supply chain integration throughout Asia, leading to different sets of rules for operating with either powerhouse. Earlier this month, former U.S. Treasury Secretary Hank Paulson warned of an “Economic Iron Curtain” dividing the world if the two countries can’t reach a deal.

Southeast Asian countries have long sought to balance the world’s major powers to avoid getting caught in another conflict like the Vietnam War. That strategy has underpinned stability that has made the region one of the world’s growth drivers, leading to increased trade with China as well as closer security ties with the U.S. to hedge against Beijing’s expansive territorial claims.

Lee warned that the rules-based multilateral order is “fraying” and called for greater economic integration in the region. He said Asean tries to be friends with all major powers, and needs to understand where it may need to make a choice between them.

“If you’re talking about economic cooperation, theoretically that is win-win,” Lee said. “But if the global economy pulls apart into different blocs,” he added, “then Asean will be put in a difficult position.”

To contact the reporters on this story: Michelle Jamrisko in Singapore at mjamrisko@bloomberg.net;Jason Koutsoukis in Singapore at jkoutsoukis2@bloomberg.net

To contact the editors responsible for this story: Daniel Ten Kate at dtenkate@bloomberg.net, Edward Johnson

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