MOSCOW, February 8 - RAPSI. The Federal Antimonopoly Service will set within one or two months TNK-BP's fine under the "third wave" of antitrust cases, the service's deputy head Anatoly Golomolzin told RIA Novosti.

He added that the antitrust authority has received a letter from TNK-BP admitting to the violations and describing its measures to rectify the situation. This will be regarded as a mitigating circumstance in determining the fine amount, he said.

The watchdog said earlier that TNK-BP might be charged the largest fine in the third wave of antitrust cases against vertically-integrated oil companies. The service was expected to fine Rosneft 1.75 billion rubles ($58 million), Gazprom Neft 979.3 million rubles ($32.5 million), Bashneft 778 million rubles ($26 million) and LUKOIL 609 million rubles ($20 million).

The antimonopoly service found TNK-BP guilty of manipulating fuel prices and imposing unfair conditions on the fuel market last spring. TNK-BP admitted imposing unfair conditions.

The third wave was initiated in February 2011. The watchdog found Rosneft, LUKOIL, Gazprom Neft and TNK-BP guilty of breaking antitrust law and manipulating diesel and jet fuel prices between the fourth quarter of 2010 and early 2011.

The same companies were punished in the first two waves in 2008-2009. Their fines totaled roughly 26 billion rubles ($864 million). Later, the watchdog reduced its claims to 15 billion rubles ($499 million) as a result of several settlement agreements.