Russia is shipping more oil than Iran to China for the first time since at least 2004 after the world’s largest energy user financed a pipeline and field expansion in the former Soviet Union to secure fuel supplies.

China, which will account for a third of this year’s global growth in oil demand, boosted imports from Russia by 37 percent in the first seven months of 2012, according to the Beijing- based General Administration of Customs. Exports from Iran dropped 22 percent in the same period as the Islamic Republic’s output slumped and international sanctions took effect.

Russia started its first pipeline shipments to Chinese buyers at the beginning of 2011 following the completion of a link that the nation’s Premier Wen Jiabao agreed to help fund in 2008 as part of a $25 billion program. He also presided over Cnooc Ltd.’s $15.1 billion bid this year for Nexen Inc., the biggest overseas takeover by a Chinese company that has assets in the North Sea, Canada, the Gulf of Mexico and Nigeria.

“The Chinese are happy to get oil wherever they can,” Ehsan Ul-Haq, senior market consultant at KBC Energy Economics in Walton-on-Thames, England, said by phone on Aug. 28. “We’re currently seeing them import Urals from Europe despite high prices,” he said, referring to the benchmark Russian export crude blend.

Urals crude in the Mediterranean rose 17 percent from the end of June to $112.21 a barrel Friday while London-traded Brent futures, used to price for more than half the world’s oil, climbed 16 percent to $113.38 in the same period. Urals in that region traded at an average 96 cents less than Dated Brent this year, compared with a $1.69 discount in 2011, data compiled by Bloomberg show.

Wen has been working to secure the supply of energy and other commodities for the nation’s growing economy since coming to power nearly a decade ago. China Petrochemical Corp., Asia’s biggest refiner, paid $8.4 billion for Addax Petroleum Corp. in 2009, gaining crude reserves in West Africa and Iraq’s semi- autonomous Kurdish region. Chinese energy companies bid at least $16 billion last year for overseas oil and gas assets that include stakes in Brazil’s offshore discoveries, data compiled by Bloomberg show.

Iranian shipments to China averaged 433,000 barrels a day in the first seven months of the year compared with 500,000 barrels from Russia, according to Bloomberg calculations from customs data from Aug. 21.

Iran shipped 41 percent more crude to China than Russia last year, China’s customs data shows. Its exports exceeded those of Russian producers every year since at least 2004, when Bloomberg started collating the data.

“China will invest in overseas energy and mineral resource development projects to secure long-term, stable, reasonable and secure supplies of energy and resources,” the Beijing-based National Development and Reform Commission, the country’s top economic-planning agency, said July 24 in a 23-page state plan.

The nation overtook the U.S. as the world’s biggest energy user in 2009, according to International Energy Agency estimates. China’s consumption will rise by about 2.6 percent this year to 9.48 million barrels a day, equivalent to almost 11 percent of global demand, IEA data show.

Wen has met with Russian President Vladimir Putin at least 17 times, agreeing in 2008 to partly finance the 300,000 barrel- a-day crude pipeline to Daqing in the country’s northeast oil hub that opened last year. OAO Rosneft, whose Vankor field was developed to help supply Asian markets, was also a beneficiary of the $25 billion in Chinese credit.

“This is an important project because we are beginning to diversify the delivery of our energy resources,” Putin, then serving as prime minister, said at the opening ceremony in Skovorodino, where the Chinese spur meets the East Siberia Pacific Ocean, or ESPO, pipeline. “Thus far, shipments were made to our European partners.”

Putin has called for Russian producers to maintain output at more than 10 million barrels a day for at least the next decade. He lowered the tax rate on crude exports last year to spur production and ordered new tax breaks to develop the country’s continental shelf.

Russia, already pumping crude at a post-Soviet record, plans to extend the ESPO pipeline to the port of Kozmino on the Pacific Coast and double its capacity by the end of this year. OAO Transneft plans to export about 21 million metric tons, or 420,000 barrels a day, from the port in 2013, Igor Dyomin, a spokesman for the pipeline operator, said by phone from Moscow on Aug. 29. That compares with 318,000 barrels a day in September, a loading schedule obtained by Bloomberg shows.

“ESPO makes it so that it costs about the same to ship crude east from central Siberia as it is to send it west,” Dyomin said. “Creating a surplus of capacity will help Russian oil become more valuable.”

The nation produced 10.32 million barrels a day in July, within 30,000 barrels of the post-Soviet high reached in October last year, according to the its Energy Ministry. Iranian crude output dropped to 2.9 million in July, according to an Aug. 10 report from the IEA in Paris. That’s near the lowest in 22 years, according to the adviser’s estimates.

“Russia has always been looking east, proactively venturing into this new export horizon,” Andrey Kryuchenkov, an analyst at VTB Capital, the investment-banking unit of Russia’s second-biggest lender, said in an email on Aug. 29.

China’s imports of Iranian crude fell to the lowest level in three months in July as U.S. and EU sanctions targeting the Gulf state’s oil sales were implemented. Russia, a supplier of arms to Iran until two years ago, has criticized the EU sanctions, defending Iran’s right to pursue a civilian nuclear program.

“The Russians are reluctant to say that they’ll ship less crude to Europe, but when the second phase of the ESPO is turned on, that’s exactly what we will see,” Ul-Haq said.