MOSCOW, Aug 30 (Reuters) - Rosneft, Russia's largest oil producer, said on Wednesday its output of oil and gas condensate dipped in the second quarter from the previous three-month period due to an agreement with OPEC+ group of oil producers to curb production.

The quarterly production dropped 2.2% to 3.9 million barrels per day, Rosneft said, adding that its first-half sales reached 3.9 trillion roubles ($41 billion), down by more than a quarter from the previous year due to weaker oil prices. Revenue in the reported quarter increased 12.1% to 2 trillion roubles.

Earnings before interest, taxes, depreciation and amortization (EBITDA) in the January-June period declined 5.1% to 1.4 trillion roubles.

The drop in EBITDA was less pronounced than the revenue slump due to an increase in sales to Asia, the company said, mainly to India and China.

The company, led by Igor Sechin, a long-standing ally of Russian President Vladimir Putin, said on Tuesday its January-June net income reached 652 billion roubles, without providing comparable figures.

($1 = 95.4205 roubles) (Reporting by Vladimir Soldatkin and Olesya Astakhova; Editing by Jacqueline Wong and Sherry Jacob-Phillips)