"Trade war is the most stupid thing in this world," Ma said Monday at a conference in Shanghai hosted by the Chinese government, CNN reports.
It's the latest and perhaps bluntest barb about the trade conflict from the co-founder and executive chairman of Alibaba (BABA), China's biggest internet company. In September, he blamed it for derailing his highly ambitious promise to create 1 million new US jobs.
The United States and China have slapped heavy new tariffs on huge swathes of each other's exports this year. The US government accuses China of stealing American intellectual property and forcing US firms to handover valuable tech. But US President Donald Trump has also repeatedly complained about his country's $375 billion deficit in the trade of goods with China.
Ma argued Monday that the purpose of trade should be to promote peace and communication rather than conflict, and that the rise of protectionism is misguided.
"Nobody can stop the free trade," he said.
His remarks at the Shanghai event came hours after Chinese President Xi Jinping — in a veiled swipe at Trump — slammed a "winner-takes-all" approach to international trade. The conference, the China International Import Expo, was organized by the Chinese government to promote the country as a market for imports from other countries.
Investors are hoping a planned meeting between Trump and Xi at the G20 summit in Argentina later this month will help ease the trade tensions.
But Ma warned in September that the conflict between the two economic superpowers could last decades. He also acknowledged that it's hurting Alibaba's business, which benefits from the flow of goods across borders.
Soon after Trump's election victory, Ma met him in New York and made the lofty pledge to create US jobs by helping American small businesses sell their products to consumers in China and elsewhere in Asia.
But in September, he said the plan — which some analysts had doubted from the start — was no longer possible.
"This promise was on the basis of friendly China-US cooperation and reasonable bilateral trade relations, but the current situation has already destroyed that basis," Ma told China's official news agency Xinhua. "This promise can't be completed."
Shares in Alibaba are down more 30% from an all-time high in June.
