LukOil Overseas has agreed to transfer 10% of its interest in the Karachaganak oil and gas condensate field to Kazakhstan's state-owned KazMunaiGas.
LukOil is part of a consortium which has sold the interest for $3bn.
Of the total consideration, the contracting parties will be responsible for paying taxes worth $1bn to the budget of the Republic of Kazakhstan.
To finance the acquisition of the stake, the consortium will accommodate KMG with a loan of $1bn, on market conditions, to be repaid over a period of three years.
LukOil Overseas president Andrey Kuzyaev said: "The agreements reached will form a basis for a new stage in the development of the Karachaganak project, with greater investments, higher production and sales of gas, and with a longer plateau in the production of liquid hydrocarbons."
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