Former President Donald Trump launched a scathing attack on fellow billionaire Mark Cuban on Saturday, accusing him of being a “loser” and a “weak and pathetic bully.”

What Happened: Trump escalated his public feud with Cuban after the latter’s criticism of the ex-president’s tariff proposals during a Kamala Harris campaign rally in Wisconsin the previous Thursday.

Trump used his Truth Social platform on Saturday to lash out at Cuban. "Mark Cuban is a Loser," Trump wrote.

"Wouldn't take his phone calls anymore while at the White House, and he went rogue. A weak and pathetic ';bully,' he's got nothing going. Really low clubhead speed, a total non-athlete!"

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Why It Matters: Trump’s proposed tariff plan, which suggests a 20% universal tariff on all imports and a 60% rate for Chinese imports, has faced widespread criticism from economists. They contend that such a stringent approach would primarily impact U.S. importers and consumers.

Interestingly, Cuban, who had once lauded Trump in 2015 as the “best thing to happen to politics in a long time,” has since turned into a staunch critic of the former president. He publicly endorsed Hillary Clinton in the 2016 election and has been a consistent supporter of the Harris campaign in the current election cycle.

Cuban, known for his role in “Shark Tank,” has also hinted at his political aspirations, including the possibility of replacing Securities and Exchange Commission Chair Gary Gensler. In a parallel development, Trump has roped in Elon Musk as a high-profile campaign surrogate, adding another dimension to his rivalry with Cuban.

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