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By Marianna Parraga
Feb 7 (Reuters) - Venezuela's state-run PDVSA has started mixing its extra heavy oil with domestic Santa Barbara light crude due to a shortage of imported diluents following U.S. sanctions imposed last week, two people with knowledge of the matter said on Thursday.
PDVSA typically imports some 100,000 barrels per day (bpd) of naphtha, mostly from the United States, to dilute up to 400,000 bpd of extra heavy oil produced by joint ventures at the vast Orinoco Belt, Venezuela's largest producing region, and make it exportable.
But the new sanctions imposed on PDVSA, which are aimed at diverting oil revenue away from the hands of socialist President Nicolas Maduro, bar U.S. exports of diluents to Venezuela. They also limit transactions with PDVSA in U.S. dollars or by companies registered in the United States.
The measures have led to an armada of anchored tankers off Venezuelan waters, which were loaded with PDVSA's crude but have been unable to complete deliveries until new escrow accounts controlled by opposition leader and self-proclaimed president Juan Guaido's team are available to receive the sale proceeds.
The Orinoco Belt's joint ventures, involving PDVSA, U.S.-based Chevron Corp, France's Total, Norway's Equinor and Russia's Rosneft, turn Venezuela's extra heavy oil into exportable grades by using crude upgraders, but a large portion of output is frequently mixed with imported diluents if upgraders are not in service or operating partially.
PDVSA received its most recent import of naphtha, supplied by a unit of India's Reliance Industries, at Jose port on Jan. 29 after firms involved in the sale were forced to discharge under a court order, according to sources close to the case and Refinitiv Eikon data.
If imported diluents including naphtha are not available, PDVSA is forced to use the little production of light crude the country has for mixing with its extra heavy oil so exportable grades can be formulated.
The crude blends resulting from mixing extra heavy oil with Santa Barbara crude are being delivered to PDVSA by most joint ventures, allowing the Venezuelan oil company to export them without violating U.S. sanctions, the sources added.
Before sanctions, oil production coming from all joint ventures was independently exported by the partnerships to generate their own cash flows.
Reporting by Marianna Parraga; Editing by Gary McWilliams and Rosalba O'Brien