Global oil supplies fell by almost 400,000 b/d in August to 84.9m b/d, according to the IEA. Non-Opec production was responsible for the dip, falling by 450,000 b/d, although a rise of 55,000 b/d in Opec output, to 28.81m b/d, partially offset this. August production was 1.25m b/d lower than in August 2008. The IEA still expects non-Opec output to grow in 2010, from 51m b/d to 51.5m b/d, largely because of increases from Russia, China and the US. Higher crude oil prices, optimism about the outlook for the global economy and indications of falling upstream costs are all encouraging developers in non-Opec producing countries, the IEA said. Total oil demand in 2009 and 2010 will be 84.4m b/d and 85.7m b/d, respectively - for both years a 0.5m b/d increase over the previous IEA forecast. However, Russia's monthly oil production exceeded 10 million barrels per day in September for the first time. Russia, now the world's largest oil producer, pumped 10.01 million barrels per day last month, up 0.4 percent from the 9.97 million bpd produced in August, which was also a record high at the time, Energy Ministry data released on Friday showed. Russian production has recovered in 2009 after suffering its first drop in a decade last year. The latest spike in output follows the August launch by state-controlled industry leader Rosneft of its massive Vankor operation in the Arctic. But analysts said Russia's position as top producer might be temporary, as mature deposits in western Siberia run dry quicker than the country's oil majors can replace them with new finds. “The pick-up seen today is the result of prior years' investment,” said Chirvani Abdoullaev, senior oil and gas analyst at Alfa-Bank. “It's only sustainable until new fields reach a plateau.” Russia has emerged as the undisputed leader in world oil production this year after the Organization of the Petroleum Exporting Countries agreed to cut supply by 4.2 million bpd from September 2008 in a bid to prop up falling oil prices. OPEC has kept official output targets unchanged at meetings since, most recently on Sept. 9. Oil prices have risen over 50 percent this year to trade just shy of $70 a barrel. Russia's oil-heavy economy, in its first recession for a decade, has benefited from the recovery in prices. The country has grabbed market share from OPEC and analysts have estimated Moscow has gained over $20 billion from the grouping's cuts. President Dmitry Medvedev said on Thursday that $80 to $90 a barrel would be a fair price for oil in the current economic climate. Crude traded at a record $147.27 a barrel in July 2008. “Russia has no interest in an endlessly high oil price. If it were to cost that much, we'd never change the structure of our economy,” Medvedev said at a meeting on the farm industry. “We haven't done anything in the last 10 years because oil kept rushing higher and higher,” he said. “When the collapse came, we felt it harder than other countries.” Before this August, Russia's previous monthly record for oil production was the 9.93 million bpd achieved in October 2007. Rosneft led September's record haul, producing 2.40 million bpd, up from 2.39 million bpd in August. LUKOIL, its closest peer, produced 1.84 million bpd, ministry data showed. Production sharing pacts, involving international energy majors such as ExxonMobil Corp and Royal Dutch Shell, also raised output by 8.6 percent to 283,329 bpd. Russian production has been boosted by the launch of Vankor and several other new fields, including LUKOIL's South Khlychuyu deposit and the Uvat, Kammenoye and Verkhnechonskoye fields owned by No. 3 Russian oil producer, TNK-BP. Vankor is expected to pump 220,000 barrels per day by the end of this year, rising to 510,000 bpd when production peaks in 2014. Russia, however, faces a major challenge sustaining output growth. Its main producers are lobbying for tax breaks they say will make investment in remote deposits viable. “We still have a problem in mature producing regions like West Siberia, where investing in upstream projects is not commercially viable unless we see more changes in the taxation regime,” Abdoullaev said. Russia, the world's largest gas producer produced 1.52 billion cubic meters (bcm) per day last month, up 8.6 percent from August, the Energy Ministry data showed.