UPDATE 1-Russia's Gazprom Neft oil reserves soar in 2007

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MOSCOW, Feb 6 (Reuters) - The oil arm of Russian gas export monopoly Gazprom (GAZP.MM), Gazprom Neft, found over four times more oil than it produced last year, it said on Wednesday adding that the figure was even higher with acquisitions.

Gazprom Neft (SIBN.MM) said in a statement its oil and gas condensate recoverable reserves rose by 148 million tonnes last year under the Russian C1+C2 classification compared to production of 32.7 million tonnes.

It said it represented a 386 percent replacement ratio, although Reuters calculations showed replacement stood at 353 percent. Any of the two figures would be the highest organic replacement ratio by any Russian company in the past years.

Last year, Gazprom Neft also acquired half of Tomskneft oil unit - which has total reserves of 415 million tonnes - from oil major Rosneft (ROSN.MM) as well as several deposits for exploration at state auctions.

With half of Tomsneft's reserves of 207.5 million tonnes and some 23 million tonnes of newly acquired deposits last year's additions would be as high as 378.5 million tonnes or 2.78 billion barrels.

Gazprom Neft has been fighting falling production since its purchase by Gazprom from the former owner, billionaire Roman Abramovich, in 2005. Last year's production was flat on 2006.

The company plans to almost double output by 2020.

Gazprom Neft's shares were down 1.12 percent by 1335 GMT, slightly underperforming the broader market .

The firm gave no figure for its overall reserves and added gas reserves increased by 8 billion cubic metres last year. (Reporting by Tanya Mosolova)