A government relations manager at Anglo-Russian oil firm TNK-BP has been arrested on suspicion of fraud, the Russian Interior Ministry and the company said on Friday.

The arrest of Igor Korneyev, who TNK-BP said had worked at the company for three months, comes after state-controlled oil major Rosneft made offers totalling over $50 billion to take over Russia's No.3 oil firm.

TNK-BP is a 50-50 joint venture founded in 2003 between Britain's BP and a quartet of Soviet-born billionaires.