- Warren Buffett tells CNBC the recent craze over bitcoin and other cryptocurrencies won't end well.
- "When it happens or how or anything else, I don't know," the billionaire Berkshire Hathaway chief says.
- But he says he would not take a short position on bitcoin futures.
Billionaire investor Warren Buffett told CNBC on Wednesday the recent craze over bitcoin and other cryptocurrencies won't end well.
"When it happens or how or anything else, I don't know," he added in an interview on CNBC's "Squawk Box" from Omaha, Nebraska. "If I could buy a five-year put on every one of the cryptocurrencies, I'd be glad to do it but I would never short a dime's worth."
Also on the show, Buffett's right-hand man, Charlie Munger, also blasted frothiness in bitcoin — and in venture capital funding.
Earlier Wednesday, the Omaha-based conglomerate announced the appointment of two new vice chairs. Gregory Abel, 55, will be vice chair of non-insurance businesses. Ajit Jain, 66, will be vice chair of insurance operations.
Buffett said he would not take a short position on bitcoin futures.
"We don't own any, we're not short any, we'll never have a position in them," he said.
"I get into enough trouble with things I think I know something about," he added. "Why in the world should I take a long or short position in something I don't know anything about."
Exchange operators such as CME Group and Cboe Global Markets have opened their platforms to allow bitcoin futures trading.
The price of bitcoin declined 3.69 percent to $13,907 Wednesday, according to data from industry website CoinDesk. The digital currency is up more than 1,500 percent in the past 12 months.
Buffett's comments came a day after J.P. Morgan Chase Chairman and CEO Jamie Dimon backpedaled his earlier criticisms of cryptocurrencies. In September, Dimon called bitcoin a fraud.
—Reuters contributed to this report.
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