Tesla (TSLA) stock extended a two-day slide on Thursday as the very public fallout between its CEO Elon Musk and President Trump escalated and Trump threatened to slash government contracts and subsidies key to Musk’s businesses.

“The easiest way to save money in our Budget, Billions and Billions of Dollars, is to terminate Elon’s Governmental Subsidies and Contracts. I was always surprised that Biden didn’t do it!” Trump wrote on Truth Social.

Earlier in the day, Trump tore into Musk from the Oval Office after days of the Tesla CEO’s public protests against Trump’s giant tax bill working its way through Congress.

“I’m very disappointed, because Elon knew the inner workings of this bill better than almost anybody sitting here, better than you people,” Trump said to reporters in the Oval Office on Thursday. “All of a sudden, he had a problem, and he only developed the problem when he found out that we’re going to have to cut the EV mandate.”

Tesla stock fell to session lows on Thursday afternoon as the two traded barbs, falling as much as 15% near 3 p.m. ET.