Adds context, details from paragraph 2 onwards, byline

By Mayela Armas

CARACAS, Nov 20 (Reuters) - Venezuela's National Assembly on Thursday approved a 15-year extension of the joint ventures between state company PDVSA and a unit of Russia's Roszarubezhneft that operate two oilfields in the South American country's western region, according to a session broadcast on TV.

The partnerships may continue operating the Boqueron and Perija oilfields through 2041 with the goal of producing some 91 million barrels or 16,600 barrels per day of crude, said lawmakers before approving the extension. The total investment is estimated at about $616 million.

The agreement was signed between PDVSA and Roszarubezhneft's Moscow-based unit Petromost, two lawmakers told Reuters.

Roszarubezhneft, owned by a unit of the Russian Ministry of Economic Development, was incorporated in 2020 and soon afterwards acquired the Venezuelan holdings of Russian state-run oil company Rosneft ROSN.MM as Washington imposed sanctions on two of Rosneft's units for trading Venezuelan oil.

Venezuela's PDVSA also remains under U.S. sanctions , which in recent years have limited foreign investment and partners willing to do business in the South American country.

(Reporting by Mayela Armas and Deisy Buitrago; Writing by Marianna Parraga; Editing by Richard Chang)

((marianna.parraga@thomsonreuters.com; +1 713 371 7559; Reuters Messaging: @mariannaparraga))