Miners build up FTSE

Xstrata has gained 2.6% to 2,035p, Kazakhmys has advanced 2.3% to 1,165p and BHP Billiton has climbed 1.9% to 1,150p. Cairn Energy has gained 3.5% to 2,407p after Merrill Lynch upgraded its stock recommendation on the company to "buy" from "neutral". The brokerage cited expected positive news flow in exploration and development from the company in the months ahead. BP has gained 1.3% to 685.5p, as oil traded above $73 a barrel in New York on speculation US economic growth may boost energy demand as the dispute over Iran's nuclear research threatens shipments. Royal Dutch Shell has add...