Warren Buffett's Berkshire Hathaway said that first-quarter profit tumbled 64 per cent, hurt by $1.6 billion of pre-tax losses tied to derivatives contracts.

The company's net income fell to $940 million, or $607 per Class A share, from $2.6 billion, or $1,682, a year earlier.

Operating profit fell 13 per cent to $1.93 billion, or $1,247 per share, from $2.21 billion, or $1,434.-Reuters