Russian oil major OAO Gazprom Neft (SIBN.RS) may become the sole owner of Tomskneft, if it exercises an option to buy a 50% stake in the oil producer from its larger peer OAO Rosneft (ROSN.RS) in 2011, a Gazprom Neft spokeswoman said Monday.

Russian oil major OAO Gazprom Neft (SIBN.RS) may become the sole owner of Tomskneft, if it exercises an option to buy a 50% stake in the oil producer from its larger peer OAO Rosneft (ROSN.RS) in 2011, a Gazprom Neft spokeswoman said Monday.

If Gazprom Neft, the oil arm of state-controlled gas firm OAO Gazprom (GAZP.RS), now owns half of Tomskneft and could, if it exercises the option, boost its output by around 115,000 barrels of oil a day.

Last year, Tomskneft produced 83.3 million barrels of oil and gas condensate and 1.72 billion cubic meters of gas.

Tomskneft used to belong to Yukos - formerly Russia's biggest oil producer - but was purchased by Rosneft in May 2007 in a bankruptcy auction. In December that year, Rosneft sold 50% of the shares to Gazprom Neft.

Tomskneft holds 1.33 billion barrels of oil equivalent in reserves as of Dec. 31, 2008.

Rosneft declined to comment.