Mr Buffett made his assessment before tens of thousands of Berkshire shareholders attending the conglomerate's annual meeting on Saturday in Omaha, Nebraska.
Charlie Munger, Berkshire's vice chairman and long-time Buffett collaborator, said during the meeting that trading in cryptocurrencies is "just dementia".
He says he hopes more daily newspapers can find a way to be economically viable because they are so important to society. Commenting on the semi-retired role of Buffet, he said,"He sits around reading most of the time and thinking, and every once in a while he talks on the phone". "I never would have thought it could have happened", Buffett said.
A cutout of Warren Buffett is seen among Berkshire Hathaway shareholders on the exhibit floor at the CenturyLink Center in Omaha, Neb., Friday, May 4, 2018, where Berkshire brands display their products and services. Its insurance and utility businesses typically account for more than half of the company's net income.
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"We have a lot of common interests, and like any two big economic entities, there are times when there'll be tensions, but it is a win-win situation when the world trades", the investor said. Buffett said the investment "has being doing so well lately". The company also has major investments in such companies as American Express, IBM and Wells Fargo & Co.
Buffett doesn't plan to retire, even though he's 87 years old, but he invited more questions about his eventual successor earlier this year when he promoted Greg Abel and Ajit Jain to vice chairmen and expanded their responsibilities.
"I have no reason to think that Wells Fargo, going forward will be anything other than a large, well-run bank", Buffett said.
A day after multinational conglomerate Berkshire Hathaway acquired another 75 million shares of Apple, its CEO Warren Buffett said the iPhone maker should spend more cash buying its own shares.