Jamie Dimon is having second thoughts about wading in to the bitcoin controversy.

The JPMorgan Chase chief executive officer, who earlier called the cryptocurrency a "fraud," said Tuesday he wishes he hadn't dismissed the technology in such broad terms.

"I regret making" those comments, Dimon said in an interview with the Fox Business network. "The blockchain is real. You can have crypto yen and dollars and stuff like that."

In September, Dimon said bitcoin was "worse than tulip bulbs," and threatened to fire any trader who bought or sold them for being "stupid." The 61-year-old CEO said Tuesday he's still not very interested in the subject, and thinks that government intervention may eventually hamper bitcoin's growth and acceptance.

JPMorgan Chase Chief Executive Officer Jamie Dimon.
JPMorgan Chase Chief Executive Officer Jamie Dimon. Bloomberg News

"The bitcoin to me was always what the governments are going to feel about bitcoin as it gets really big," he said. "I just have a different opinion than other people. I'm not interested that much in the subject at all."

The value of digital currencies have surged this year, with everyone from regulators to top bank executives taking note. The price of bitcoin, the most ubiquitous of the currencies, has more than tripled to $14,297 since Dimon made his comments in September.

Dimon reiterated in the interview that he believes in blockchain, the technology used for verifying and recording transactions that's at the heart of cryptocurrencies. Experts have said blockchain technology could reshape the global financial system and JPMorgan is testing potential use cases of the technology.

Initial coin offerings, however, "you have to look at individually," he said in the interview.

Bloomberg News