The feud is back on. Billionaire Elon Musk threatened to create his own political party, and President Trump fired back.

Shares of Tesla tumbled 7% Monday as the feud between CEO Elon Musk and Trump reignited over the weekend.

Shares of Tesla tumbled 7% Monday as the feud between CEO Elon Musk and Trump reignited over the weekend. Musk, once a top donor and ally of Trump, announced that he was forming a third political p… ...

The billionaire continued to criticize the GOP and appeared to take shots at the president after he mocked the idea of Musk creating a third-party in the U.S.