Berkshire Hathaway chairman and chief executive Warren Buffett said on Friday that his firm had eliminated most of its catastrophe insurance business in the United States.

Citing a decrease in interest rates, Buffett told cable television network CNBC: "We actually in the United States have almost eliminated our catastrophe insurance business."

Buffett also said that concerns over weaker economic growth in China and geopolitical tensions surrounding Russia and Ukraine were not a reason to sell assets.

"They're not warranted in terms of the market," Buffett said on the concerns. "I would bet a lot of money that income from a diversified group of stocks will increase significantly over the next 20 years, so the headlines will not make any difference in that," he said.

Buffett also said that the economy was not "remotely close" to another financial crisis similar to the 2008 credit crisis, and that a 50 percent decline in global stock markets would surprise him a lot.