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By Marianna Parraga and Brian Ellsworth
HOUSTON/CARACAS, Aug 21 (Reuters) - Venezuela's shipments of crude oil and fuel to its allies have fallen to a five-year low as a weak economy hits its ability to uphold accords that former President Hugo Chavez struck to lower energy costs for friends and expand his diplomatic clout.
Total shipments under cooperation deals with Latin American and Caribbean countries dropped 11 percent in 2013 to 243,000 barrels per day (bpd), the lowest level since 2007, according to recent data from Venezuela's state-owned oil company PDVSA.
Several factors are behind the decline: lower oil output and weak economic growth at home, a domestic refinery network that has not fully recovered from a severe accident in 2012, and financing agreements with China that divert much of the OPEC nation's oil production to Asia.
Some of the beneficiaries of the cheap oil are now being forced to turn to other sources.
In the eights months through August, countries from Jamaica to Argentina that have supply pacts with Venezuela have bought 140 cargoes of crude, components and fuel for transport and power generation on the open market, according to tender information compiled by Reuters.
More than two thirds of those were for Ecuador, one of Venezuela's closest allies.
The purchases, which have left tankers in short supply, are far costlier than oil obtained through long-term pacts.
Chavez, who was Venezuela's socialist president for 14 years before his death from cancer in March 2013, used the country's oil wealth to help allies and extend his political influence across Latin America and the Caribbean.
His 2005 Petrocaribe accord required members to pay cash for just 40 percent of every shipment, and let them finance the rest for 25 years at low interest rates, or make in-kind payments with products ranging from rice to blue jeans.
Twenty-one countries are party to oil pacts managed by Venezuela, including Petrocaribe, the Caracas Energy Agreement and other bilateral deals.
But mounting economic problems in the South American country have strained the programs. As far back as 2010, Venezuela had started buying fuels from third parties to meet quotas for the accords.
Since then, fuel exports has slipped further and PDVSA's financial position has weakened, limiting its ability to assist allies even though Chavez's hand-picked successor, President Nicolas Maduro, backs the deals.
"It is importing a lot to cover its own domestic demand, so buying extra volumes to assist those countries is unsustainable," said an official from a top global commodities trader involved in supplying fuel to Venezuela.
While Venezuela struggles to maintain its agreements, U.S. companies flush with natural gas are poised to pounce on new energy market opportunities that might be created by Petrocaribe's problems.
The U.S. government can also benefit as it looks to regain its influence in Latin America and the Caribbean.
U.S. Vice President Joe Biden last month announced the Caribbean Energy Security Initiative, a plan to reduce the region's reliance on "high-cost imported fuel and electricity", promising financing for projects to revamp power generation.
And the Overseas Private Investment Corp., a U.S. government agency that finances development, is in discussions with investors interested in building new energy projects in the Caribbean, according to a senior State Department official.
Venezuela now sends 485,000 barrels per day (bpd) of crude and fuels to China to service oil-for-loan deals, up 98 percent from 2010, as President Nicolas Maduro's government has become increasingly reliant on Chinese financing.
That has left fewer barrels available for regional friends.
The current quota or maximum volume that Petrocaribe members could receive is 377,000 bpd, according to PDVSA, though in 2013 it sent 134,000 bpd less than that.
Dominica, Honduras, Paraguay and Bolivia did not receive a single barrel from Venezuela last year, PDVSA data released in late June showed.
Argentina, which emerged from a deep economic crisis following its 2002 debt default in part with the help of cheap Venezuelan fuel oil, saw shipments from Venezuela cut in half last year.
Oil Minister Rafael Ramirez has denied Venezuela is offering less to Petrocaribe partners, insisting that shipments fluctuate based on the needs of each country.
"These are monthly requests and the countries have quotas. Sometimes they ask for all of it, sometimes they don't need to," he told reporters in June. "It changes, and the countries know this."
But that does not appear to be the case for countries turning to the open market, some for the first time in years, according to documents seen by Reuters.
Though governments and state-owned companies do not publish data from tenders held in the opaque world of crude trading, intermediaries say the purchases - which tend to be very expensive - are on the rise.
PDVSA and other state-run companies in the region did not respond to requests for comment.
State-run Argentine energy firm YPF is now buying on the open market a significant portion of its diesel and fuel oil needed for power generation, tender documents show. That has raised the cost of electricity subsidies even as the country again fell into a debt default last month.
"Argentina has agreed to pay this year up to $20 per million BTU for LNG imports versus an international price of $16-18," a trader said. "But consumers don't notice it because of the subsidies."
A YPF spokesman, when asked about Venezuelan supplies, said that domestic price increases are a result of higher costs, but he declined to elaborate.
Uruguay has this year been buying at least one 1 million-barrel cargo of crude each quarter on the open market after supplies from PDVSA in 2013 dropped 15 percent.
Venezuelan supplies have even declined in countries where PDVSA owns refinery assets, such as Jamaica and the Dominican Republic, exposing them to intermediaries.
Ecuador, facing a prolonged overhaul of its main refinery, has bought more than 70 cargoes of naphtha and 30 diesel cargoes so far this year after an exchange agreement with Venezuela fell to 2,000 bpd last year from 49,000 bpd in 2008.
Chavez was a vocal critic of what he called "usurious" traders and Petrocaribe was created largely to cut out the role of intermediaries that raise import costs for most countries in the region, but none of his energy pacts has been able to completely dispense of traders.
Bolivia is also struggling. It used to get most of its diesel from Venezuela, but those shipments have slipped and Chile is now its main supplier. That has exacerbated fiscal pressure from fuel subsidies that last year exceeded $1 billion, or 3.4 percent of gross domestic product.
"Any shipment reduction from Venezuela, which used to be Bolivia's main diesel supplier, will affect the public budget," said Marco Gandarillas of Bolivia's Data and Information Center, an independent think tank.
President Evo Morales has tried to raise fuel prices, which have been steady since 2001, but protests stopped him.
Other countries, such as Guatemala, sought Venezuelan supplies but never received much amid complaints about terms and political disagreements between them.
Not all countries have suffered declines, however. Shipments to Cuba and Nicaragua, two of Venezuela's closest allies, have held strong - a combined 130,000 bpd in 2013, PDVSA says.
In the United States, Citizens Energy Corp in February renewed for the ninth straight year a controversial program that distributes some 620,000 barrels of heating oil to needy families. The fuel, supplied at favorable terms, comes from PDVSA's unit Citgo.
Widening agreements with China and generous financing schemes have created a cash flow problem for Venezuela, which is struggling with inflation above 60 percent and chronic product shortages as a result of insufficient hard currency.
In those circumstances, the oil deals with allies look like a luxury that Venezuela can ill afford, especially as some countries, such as Haiti and Nicaragua, have missed payments even after Venezuela forgave some debts..
Total debts are climbing. PDVSA reported that non-current account receivables related to energy agreements increased last year to $6.09 billion, compared to $5.3 billion in 2012 and $3.25 billion in 2011.
At the same time, PDVSA did not receive cash in the short term for a third of the barrels exported in 2013 as more crude is used to service debts owed China, according to Reuters' calculations based on the company's latest financial statement.
That is a concern for a country where oil exports historically bring in 96 percent of dollars and PDVSA's transfers to the state fund a third of the budget.
"While Venezuela itself is compromising more barrels for China and importing at least eight monthly cargoes of naphtha, diesel and gasoline for its domestic market, Jamaica, Uruguay and Argentina are tendering a lot to import fuels", a trader involved in the purchases said. (Additional reporting by Enrique Andres Pretel in La Paz and Eliana Raszewski in Buenos Aires; Editing by Terry Wade and Kieran Murray)