In a Truth Social post, Trump called Cuban a “loser” and a “weak and pathetic ‘bully.’”

“Mark Cuban is a Loser. 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!” he said.

The post comes after Cuban criticized Trump’s tariff proposals at a Harris campaign rally in Wisconsin on Thursday.

“Let me just tell you, this man has so little understanding of tariffs, he thinks that China pays for them,” he said.

Trump recently defended his tariff proposals in an hourlong interview with Bloomberg, during which he directed ire at China and even allies like Japan and Germany who he said refuse to buy American cars after selling their own vehicles in the United States.

Cuban is a noted critic of Trump, but in 2015 he said Trump was the “best thing to happen to politics in a long time.”

Now, with a little over two weeks until the election, Cuban has been on the campaign trail for Harris as part of the group “Business Leaders for Harris,” which includes CEOs and small-business owners who will advocate her bid for the White House.