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CARACAS/HOUSTON, May 10 (Reuters) - A backlog of crude oil imports and exports at Venezuela's main crude-exporting port should ease once state oil company PDVSA finishes installing new loading arms at its Jose terminal towards the end of May, a union leader said on Tuesday.
Technical problems with several loading arms at Jose have since March sparked delays to load and discharge cargoes and created queues of tankers in the Caribbean.
PDVSA said in a statement earlier this month that it was installing three new loading arms to speed up operations at Jose, which loads some 70 percent of Venezuela's crude exports.
"They're saying it will be finished by the end of May," said union leader Eudis Girot, who added some of the loading arms had already been installed.
"We expect the queue of ships will start to be more fluid."
Caracas-based PDVSA did not immediately respond to a request for comment.
As of Tuesday, more than 20 vessels were waiting at Jose to load crude and discharge imported dirty products, according to Thomson Reuters vessel tracking data.
A dozen tankers more were anchored around PDVSA's Bullenbay port on the neighboring island of Curacao. British BP, which along with China Oil was awarded a tender in March to sell PDVSA some 8 million barrels of U.S. and Nigerian light crude in the second quarter, had four 550,000-barrel cargoes of U.S. West Texas Intermediate crude waiting to discharge.
The long delays - another U.S. crude cargo sent by China Oil waited 19 days at Curacao until last week - have been worrying shippers and trading firms about growing invoices for demurrage, shipbrokers and traders said.
The delays have also caused a decline in Venezuela's crude exports to the United States since March.
The export issue comes on top of significant issues at the OPEC country's refinery circuit, forcing PDVSA to import refined products as well.
Gasoline-making fluid catalytic cracking units (FCC) at Venezuela's biggest refinery, 645,000 barrel-per-day Amuay, as well as at the smaller Cardon and El Palito refineries are currently down, according to PDVSA, another union leader, and workers.
Output had already dropped at the refineries in recent months, with critics blaming shortages of spare parts, lack of maintenance and a shaky electrical grid for outages and unplanned stoppages.
PDVSA confirmed earlier on Tuesday that 146,000 bpd El Palito had been undergoing general maintenance since April 11. The refinery has enough inventory of fuels, the firm added on Twitter. (Reporting by Alexandra Ulmer in Caracas and Marianna Parraga in Houston; Editing by Cynthia Osterman)