“Shark Tank” co-stars Mark Cuban and Kevin O’Leary, aka “Mr Wonderful,” have locked horns over tariffs on China.

What Happened: On Friday, O’Leary voiced his discontent with China’s trade practices on X, formerly Twitter.

He argued for drastic action in the form of raising tariffs to 400%, saying that China has been unfair in its business practices for decades. “I can tell you firsthand they DON’T play fair.”

“I’m calling for REAL action, raise tariffs to 400%. Make it SO painful they have no choice but to come to the table,” O’Leary stated, referring to Republican presidential nominee Donald Trump’s stance on the subject.

See Also: Mark Cuban Battles Former Trump Advisor Over Ex-President’s Comments On American Auto Workers

Cuban swiftly responded to O’Leary’s call for increased tariffs, highlighting the adverse effects such measures could have on U.S. companies.

He cited a Deutsche Bank report and a Goldman Sachs survey, indicating that companies were “cutting costs, putting off investments, and paying extra to build up inventory to help cushion the impact of China tariffs.”

Why It Matters: This isn’t the first time the two “Shark Tank” co-stars have publicly disagreed. In August, they had a social media showdown following O’Leary’s controversial comments on Democratic nominee Kamala Harris, whom Cuban is publicly supporting.

Their latest disagreement comes amid a heated debate on tariffs. Last month, the Joe Biden administration hiked tariffs on Chinese goods, causing stocks of Alibaba and JD.com to drop.

Meanwhile, Trump has defended his plans to impose 200% tariffs on cars imported from China and Mexico, aiming to protect American automotive jobs. “I hope the union workers, auto workers understand that I saved their jobs.”

Previously, Harris criticized Trump’s tariff policy, naming it “Trump sales tax” during the presidential debate last month. At the time, she stated that the Trump administration contributed to a substantial trade deficit and instigated trade wars.

“Under Donald Trump’s presidency, he ended up selling American chips to China to help them improve and modernize their military,” Harris said then.

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Disclaimer: This content was partially produced with the help of Benzinga Neuro and was reviewed and published by Benzinga editors.

Photos courtesy: Gage Skidmore via Flickr and Shutterstock