Two of Wall Street's harshest bitcoin critics say investors should remain wary of the cryptocurrency.
"Just beware,“ he said.
Dimon called bitcoin a "fraud" in September and later said those "stupid enough to buy it" will one day pay the price. He said in January he regretted the "fraud" comment.
"I set a high standard. I don't know whether Jamie can top me or not," Buffett told CNBC during the rare joint interview with Dimon. The interview was recorded Wednesday.
Bitcoin has lost more than half its value since topping $19,000 in mid-December.