* Chavez questions relevance of Citgo refineries

By Marianna Parraga

CARACAS, Sept 3 (Reuters) - Venezuela is sending increasing volumes of oil exports to China that were once bound for the United States and plans to boost shipments to Asia while questioning the relevance of its refineries in North America.

The United States has long been the main buyer of crude from the South American OPEC member. But, under President Hugo Chavez, Venezuela's relations with Beijing have taken on increasing importance.

"We have been decreasing oil shipments to the United States, but that is because we've been diversifying the market ... We are already sending nearly half a million barrels a day to China," Chavez said in televised remarks on Thursday.

During June, Venezuela shipped 850,000 bpd of crude to the United States, down from 1.01 million bpd in May and an average of 917,000 bpd for the first five months of the year, according to the U.S. Energy Information Administration.

During that same month, the shipment of refined oil products fell to an historic low of 48,000 bpd -- the smallest volume since 1993, when the EIA began recording those exports.

Traders say China seems to be one of few countries to have been receiving increasing shipments of Venezuelan oil during the same period, when Venezuelan output has been declining.

China National Petroleum Corp "is maybe the most important commercial client right now for (Venezuela's state oil company) PDVSA," one trader told Reuters on Friday.

All the fuel oil being bought by China was leaving through Bonaire and the Bahamas, where PDVSA owns or operates terminals for very large crude carriers, the trader added.

TENSE TIES WITH WASHINGTON

Another major PDVSA customer, Petrochina, Asia's largest fuel oil player by volume, has put into service four VLCCs to ship about 6.6 million barrels of fuel oil from Venezuela to Singapore this month, traders said on Tuesday. [ID:nSGE67U09A]

Figures on Venezuelan oil shipments to Asia are hard to pin down, but a substantial amount -- more than 200,000 bpd -- is partly in repayment for Chinese loans, including one of about $20 billion that was agreed in April. [ID:nTOE63J06H]

While diplomatic tensions between Caracas and Washington have been simmering over a range of thorny issues, including Chavez's rejection of the newly nominated U.S. ambassador, ties with Beijing have expanded rapidly in recent years.

In February, CNPC was awarded a stake in the Junin 4 block of Venezuela's Orinoco extra heavy crude belt, which is seen as one of the world's biggest. This week, Caracas said a Chinese firm would refurbish the country's main port. [ID:nN01143383]

Venezuelans are due to vote in a legislative election on Sept. 26.

Chavez rejects statements by opposition politicians who criticize his administration's management of the sector by highlighting the fact that U.S. oil sales have been declining.

"They are crying because of that, saying it is the best market. Ha ha! Best market? PDVSA has been selling subsidized oil. We've been subsidizing the empire," he said on Thursday.

Citgo, which is PDVSA's refining subsidiary in the United States, gave Venezuelans almost no dividends, he added.

"Everything there is a perfect deal for the gringos," he said. (Writing by Daniel Wallis; Editing by Walter Bagley)