Lukoil, Russia's second-biggest oil producer, wants to sell its stake in a Russian consortium developing a large oil project in Venezuela because it is not a high priority, Lukoil's head said.
Venezuela is the world's 11th largest crude exporter but foreign companies operating there have faced price controls and currency devaluations along with threats of nationalisation, forcing several to quit the country.
Lukoil's exit could raise more questions about Venezuela's ambitious plans to boost stagnant output and the ability of the government to turn the promise of the Orinoco Belt into reality.
Lukoil is part of the Junin-6 consortium developing heavy oil in the Orinoco basin. The group is led by Russian state oil major Rosneft and also includes Gazprom Neft.
"We made an offer to the consortium to buy out our stake," Vagit Alekperov told reporters. "This is not a project of a high priority for us."
Surgutneftegas and TNK-BP, which was bought by Rosneft for $55 billion earlier this year, have also decided to leave the consortium, citing a need to focus on domestic business.
The Junin-6 consortium owns a 40 percent stake in the project, which started production in September 2012, while Venezuela's state-run PDVSA has 60 percent.
"The consortium is falling apart ... The companies have understood the political risks and begun to leave the project, one by one," Alexander Pasechnik, an analyst with the National Energy Security Fund think-tank in Moscow, said.
Some other companies have also taken flight from the Latin American country.
Last month, Malaysia's Petronas said it was exiting one of the biggest petroleum projects in the Orinoco Belt, after what sources close to the venture and within the firm said were disagreements with Venezuelan authorities and PDVSA.
Ties between Moscow and Caracas flourished under Hugo Chavez, the socialist leader who died of cancer earlier this year to be succeeded by Nicolas Maduro, who won the presidential election in April and was Chavez's chosen successor.
