Kazakhmys' ENRC blow

Copper miner Kazakhmys will this week confirm a huge writedown of about $2bn (£1.3bn) in the value of its 26 per cent stake in fellow Kazakh miner ENRC.

Last month, Kazakhmys reported a 31 per cent dive in full-year profit to $1.36bn at the non-ENRC part of its business, on the back of rising costs and falling copper prices.

ENRC has since reported its 2012 result, a dive into the red on the back of massive writedowns, which Kazakhmys has factored into its previously announced result to give a final full-year figure.

Apart from helping to drag down Kazakhmys' operating profit for the year by about 52 per cent to $816m, according to estimates by Liberum Capital, the group will also announce a writedown on its stake in the company.

That stake had a market value of $1.54bn at the end of 2012, compared with $3.3bn a year earlier.