Kazakhstan, one of the world's 10 biggest oil producers, increased pressure on international companies operating in the country on Tuesday, calling for improved contract terms. The move is the latest in a string of claims,

Chevron achieves first oil at Kazakhstan's Tengiz field, completing $48B expansion project, boosting production to 1% of global crude supply.

Chevron said on Friday that it has started producing oil from an expansion at Kazakhstan’s Tengiz oilfield, which could help lift the project’s total output to 1 million barrels per day at full capacity.

Chevron said on Friday it had started production at a $48 billion expansion of the giant Tengiz oilfield which will bring its output to around 1% of global crude supply.