The rules, which require Berkshire to report unrealized gains or losses in equity investments in net income, helped fuel a USD1.14 billion loss in the first quarter, the company said.
During the traditional Q&A session at Berkshire Hathaway's annual meeting, a shareholder challenged Buffett on his refusal to pressure Berkshire subsidiaries to divest from gun-related businesses.
Berkshire promoted Buffett's two potential successors, Greg Abel and Ajit Jain, to vice chairmen in January and gave them bigger responsibilities overseeing the company's business units.
"The US and China are going to be the two superpowers of the world, economically and in other ways, for a long, long, long time", Buffett said. Berkshire is now Apple's third largest shareholder, behind Vanguard Group and BlackRock Inc.
Earlier this week, Buffett revealed that he had bought 75 million additional Apple shares, which means that Buffett now owns approximately 5 percent of Apple.
"I love the idea of having our 5 percent, or whatever it is, maybe grow to 6 or 7 percent without our laying out a dime".
EN IMAGES - La "Fête à Macron", entre ambiance festive et revendications politiques
En effet, le député des Bouches-du-Rhône s'est emparé du micro et n'a pas hésité à pousser la chansonnette. Le premier rassemblement a eu lieu devant l'Opéra de Paris à midi.
Buffett also spoke about one of Apple's main rivals - Google - admitting it had been a mistake for Berkshire not to invest in Alphabet, its parent company, and Amazon.
"It is an unbelievable company", Buffett said in an interview with CNBC. Vetr upgraded shares of Berkshire Hathaway from a "hold" rating to a "buy" rating and set a $212.93 price objective on the stock in a research report on Monday, February 5th.
"My phone is not ringing off the hook with good deals", he said.
"It gets me first place in the queue, I think when people go to so much effort it shows Warren how important he is for us", Robertson said.
At the AGM, the company told shareholders that it had swung to a $1.14 billion loss at the end of the latest financial year, compared with a profit of $4.06 billion in the previous 12 months. U.S. regulators imposed US$1 billion of fines last month over lending abuses at the bank.
But operating earnings for the quarter rose to USD5.29 billion from USD3.56 billion in the previous year.