By Marianna Parraga and Mircely Guanipa
(Reuters) - Venezuela's oil exports fell 8% in April from the previous month amid continued delays linked to poor-quality crude grades and insufficient oil upgrading capacity available, according to documents and vessel monitoring data on Thursday.
U.S.-sanctioned Venezuela recovered a portion of lost production last year, but crude shipments have been volatile, bouncing some 200,000 barrels per day (bpd) in the space of a few months as its ability to turn its extra-heavy oil into exportable grades has waxed and waned.
State-run oil firm PDVSA and its joint ventures exported an average of 644,870 bpd of crude and refined products last month, with over 70% of shipments sent to China directly or through trans-shipment hubs like Malaysia, according to PDVSA's internal loading schedules and Refinitiv Eikon tanker tracking data.
"There are high inventories of diluted crude oil," PDVSA said in one of the reports, which showed over 4 million barrels of that grade stored versus 1.3 million barrels of Merey, the most popular crude among Asian refiners.
The company continued trying to restart a third crude upgrader, Petromonagas, to ramp up output of higher quality grades, it also said.
The April shipments included a 1.99 million-barrel cargo of Merey 16 heavy crude onboard the Iran-flagged tanker Dan, one of the schedules showed. The vessel had arrived in Venezuelan waters in February carrying Iranian condensate as part of a swap agreement supplying PDVSA much needed diluents.
Another Iranian tanker, the Derya, docked this week at Venezuela's Jose port, according to monitoring service TankerTrackers.com. It is expected to discharge some 2.1 million barrels of condensate PDVSA was expecting since March.
Iran's Oil Minister Javad Owji met his Venezuelan counterpart and President Nicolas Maduro this week in Caracas to discuss agreements. Both sanctioned by Washington, the nations have tightened their relationship through oil swaps and the supply of refining equipment and food to Venezuela.
Venezuela also shipped 186,000 bpd of residual fuel oil and over 240,000 metric tonnes of petroleum coke, sulphur and methanol in April, according to the data.
Struggling to find tankers willing to load crude at Venezuelan ports due to the sanctions, PDVSA and other state companies have recently ramped up exports of byproducts and residual fuels.
The South American country last month doubled oil exports to another key political ally, Cuba, where lines for diesel and gasoline have exposed fuel shortages this year. Venezuela sent almost 70,000 bpd of crude, diesel, gas oil, petroleum coke and fuel oil to Cuba, the data showed.
(Reporting by Marianna Parraga in Houston and Mircely Guanipa in Maracay, Venezuela; Editing by Marguerita Choy)