The full startup of a project to expand production at Chevron Corp.’s giant oil field in Kazakhstan is set to be pushed back until the end of 2024 due to delays in the final stages of the $45 billion development. 

The Tengiz Future Growth Project will expand output at Kazakhstan’s largest oil field by 260,000 barrels a day, or about 40%. The delay comes at a time when the Central Asian nation’s crude exports are of growing importance to Europe, which has banned most imports of Russian oil in response to the invasion of Ukraine.

The Tengiz expansion has gone beyond its initial budget of $37 billion and its completion date had already been rescheduled twice from the original plan of mid-2022. The latest planning scenarios are for a further delay of as much as six months to the previous target of June 2024, a Chevron spokesman said in a statement.  

“Tengizchevroil remains focused on a safe, reliable startup,” the spokesman said. “The project is forecasted to be mechanically complete this quarter. Recent commissioning progress has been slower than expected.”

The planning scenarios for a related development intended to help Tengiz maintain its base production, called the Wellhead Pressure Management Project, show that startup could be three months later than planned, the spokesman said. 

“Tengizchevroil is taking actions to mitigate schedule pressure,” the spokesman said. “Chevron will assess the impact of these actions on project progress over the next few months.”

Tengizchevroil is 50% owned by Chevron, while Exxon Mobil Corp. and state-owned KazMunayGas also hold a 25% and a 20% stake in the venture, respectively. A government draft plan published in April put the latest cost for the expansion project at almost $47 billion.