LONDON/NEW YORK (Reuters) -U.S. oil major Exxon Mobil ( XOM ) has joined rival Chevron Corp ( CVX ) in considering options to buy parts of sanctioned Russian oil major Lukoil's international assets, sources familiar with the matter said.

Exxon is considering options for Lukoil assets in Kazakhstan, where both the U.S. and the Russian firm have stakes in the Karachaganak and Tengiz fields, the sources said. Chevron ( CVX ), another partner in these assets, is also studying options to buy them, Reuters reported on Monday.

Exxon might also study a potential bid for the West Qurna 2 field in Iraq, which is operated by Lukoil and is the Russian firm's most-prized asset, two of the sources said. The U.S. company had long been the operator of the neighboring West Qurna 1 project before exiting last year.

Exxon declined to comment.

The list of potential bidders for Lukoil's global assets has been growing since the U.S. Treasury on Friday gave clearance to companies to begin talks with Lukoil. The authorization lasts through December 13.

Bloomberg reported on Exxon and Abu Dhabi National Oil Company interest in Lukoil assets earlier on Tuesday.

U.S. private equity firm Carlyle is among those exploring options to buy Lukoil's foreign assets, sources told Reuters last week.

Lukoil has three refineries in Europe, stakes in oilfields in Kazakhstan, Uzbekistan, Iraq, Mexico, Ghana, Egypt and Nigeria, and hundreds of retail fuel stations around the world, including in the United States.

The company's foreign assets extract about 0.5% of global oil, based on 2024 filing.