Exxon Mobil Corp on Wednesday (22 February) warned in a securities filing of potential risks to its Kazakhstan oil operations, which provided $2.5 billion in earnings last year.

Threats to Kazakhstan oil exports have been in the spotlight since Moscow invaded Ukraine a year ago this week. Exxon and Chevron are major holders in the Central Asia country’s oil production and related export pipeline.

Kazakhstan shares a 4,750 mile (7,644 km) border with Russia and its oil exports travel mainly through a Caspian Pipeline Consortium (CPC) line through Russia and lands at a Russian Black Sea export terminal.

Russia shuts down terminal after Kazakhstan offers to send more oil to the EU

A Russian court closed a key oil terminal for the export of Kazakh oil on 6 July, two days after the President of Kazakhstan told Council President Charles Michel that his country is ready to send more oil to the EU.

Any closure of the CPC pipeline or terminal would shut in more than 1% of global oil supply and cost its producers billions of dollars in lost income.

Exxon said its stake in Kazak oil fields produced 246,000 barrels of oil and gas per day last year. That oil provided after-tax earnings of about $2.5 billion, the filing said.

Exxon “could experience a loss of cash flows of uncertain duration from its operations in Kazakhstan,” the filing said, if oil exports through the CPC pipeline are “disrupted, curtailed, temporarily suspended.”

The US oil major owns a 25% interest in the Chevron-led Tengizchevroil (TCO) oil production joint venture, which controls the Tengiz and Korolev oil fields in Kazakhstan, and a 16.8% working interest in the Kashagan field.

Chevron produces around 380,000 bpd, or more than 12% of its total output from Kazakhstan. The company aims to boost total output by 40% at Kazakhstan’s largest field Tengiz, to around 1 million bpd.

Last month, Chevron finance chief Pierre Breber said its 2022 Kazak production lost less than 10,000 barrels a day on average from temporary outages.

“We have risks in our business, everywhere. And of course, we manage those risks,” Breber said. “I can’t predict the future but CPC was very reliable in 2022.”

London-based Shell PLC and Italy’s Eni also have stakes in the CPC.

Exxon’s filing showed its global workforce fell by 1,000 last year to 62,000 employees as it continued to cut costs and boost shareholder returns. It was the third year in a row Exxon reduced its workforce.