UPDATE 1-Lukoil net profit doubles on higher sales, acquisition
* Q2 net income at $2.1 bln vs $2.25 bln in analyst poll
* Lukoil acquired Samara-Nafta in April (Adds detail, share price)
MOSCOW Aug 30 (Reuters) - Russia's No. 2 oil producer, Lukoil, posted a doubling in second-quarter net income on Friday, just missing forecasts as a weaker rouble and higher-than-expected taxes dampened a rise in sales and the impact of an acquisition.
Lukoil said its second-quarter net income jumped to $2.1 billion, flattered by a weak performance in the same period last year when earnings were hit by a higher tax bill. However, that missed analysts' average forecast of $2.25 billion.
Lukoil has been struggling with a decline in oil production at its depleted fields in Western Siberia, which account for more than a half of its resource base.
To stem the decrease, the company has bought into foreign assets, including Iraq's West Qurna-2 project. In April, it also acquired Russia's Samara-Nafta oil producing company from Hess Corp, boosting second-quarter results.
Lukoil's shares were down 1 percent in early trade, lagging a 0.5 percent slide in the broader market.
Rosneft, Russia's top oil company, last month reported a $1.1 billion second-quarter net profit on a margin of 3 percent. That compares with Lukoil's 6 percent, according to Reuters calculations.
Lukoil said second-quarter sales rose 8 percent to $35 billion from $32.4 billion in the year-earlier period. Analysts had expected sales to be flat.
Earnings before interest, taxation, depreciation and amortisation (EBITDA) rose 26 percent to $4.36 billion, in line with expectations. (Reporting by Vladimir Soldatkin; Editing by Lidia Kelly and Mark Potter)