The value of the transaction was determined by reference to the price paid by Kazakhmys when it acquired the Ekibastuz plant in May 2008, plus subsequent investments in the business by Kazakhmys.

The transaction follows a memorandum of understanding, signed in October 2008, between Kazakhmys and Samruk-Energy, a subsidiary of Samruk-Kazyna, to consider a partnership at Ekibastuz.

The consideration of $339m will be payable in cash and will primarily be used by Kazakhmys to repay debt. The transaction is subject to regulatory consents and approvals and completion is expected by the end of 2009.

Kazakhmys will retain management control of Ekibastuz following the transaction. The board believes that partnership with Samruk-Kazyna will enhance the value of Ekibastuz by providing a relationship with the Bogatyr mine (jointly owned by Samruk-Energy and UC Rusal).

The partnership is also expected to further support the upgrading of the Ekibastuz power station, while providing integration with Kazakhstan’s generation and transmission programmes.

Oleg Novachuk, chief executive of Kazakhmys, said: “Samruk-Kazyna is an excellent partner for us in Ekibastuz and we are pleased to be formalising the relationship. Ekibastuz is a key strategic asset in Kazakhstan and this agreement will assist its longterm development and return to full capacity.”

The Government of Kazakhstan owns Samruk-Kazyna.