A Siberian court on Friday piled more legal pressure on BP by ordering the British group to pay $3.1 billion in damages for its attempted Arctic oil exploration tie-up with the state giant Rosneft. The ruling comes as BP holds direct negotiations with Rosneft, Russia\'s largest oil firm, to buy out the British firm\'s stake in the troubled TNK-BP joint venture it co-owns with four local tycoons. A lawyer for plaintiff Andrei Prokhorov said the court\'s 100-billion-ruble ($3.1-billion) ruling came against London-based BP plc and the group\'s BP Russia Investment Limited venture. \"We are fully satisfied,\" attorney Dmitry Chepurenko said by telephone from the oil-producing region of Tyumen. \"For us, this decision was not a surprise.\" Prokhorov, a minority shareholder, had reduced demands in his suit to $8.9 billion from the original sum of $12.5 billion on account of a drop in the price of oil since the day the initial agreement was first signed in January 2011. Prokhorov has always denied he was acting in the interests of the four powerful Soviet-era billionaires who operate their half of the company through the Alfa Access Renova (AAR) consortium. AAR successfully blocked the deal in a European court of arbitration by arguing that BP had an obligations to offer TNK-BP priority rights to any operations it would like to conduct across the country. Prokhorov said TNK-BP Holding lost potential profits by being shut out of the $16 billion share-swap and joint exploration venture. The Arctic deal eventually went to the US super-major ExxonMobil. The ruling will make no immediate financial impact on BP because it can still fight the ruling in higher courts -- a process that Prokhorov\'s attorney said could take \"at least\" six months. But it will also remind BP of the other court battles it has waged -- and often lost -- in Russia when facing complications with either its tycoon partners or the state. A BP attorney immediately denounced the ruling as a \"corporate attack\" that demonstrated the court\'s subservience to the government\'s wishes. \"This court ruling seriously damages the Russian court system\'s reputation and proves its inability to defend honest investors against illegal corporate attacks,\" BP lawyer Konstantin Lukoyanov told the RIA Novosti news agency in Tyumen. \"All of the plaintiff\'s claim are based on absurd assumptions that have nothing in common with the interests of TNK-BP or its shareholders,\" the BP lawyer said. Prokhorov owns just a small handful of shares in the venture\'s holding company and most economists agree that his case would have never survived either the European or US court systems. The controversial claim had already been rejected once in November -- a move that came just two months after British Prime Minister David Cameron addressed the issue with Russia\'s ruling tandem of Vladimir Putin and Dmitry Medvedev. But the case was picked up again this year just as BP was entering another war of words with the AAR billionaires over future TNK-BP strategy and dividend payments. BP eventually put up its half of Russia\'s third-largest oil company for sale in July 1 and received a quick bid from the tycoon\'s themselves. Rosneft entered the fray as expected this week and has three months to negotiate an agreement that could see BP lose an instant cash source that has provided $19 billion in dividend payment\'s since TNK-BP\'s creation in 2003. Analysts believe BP views a deal with Rosneft as a way of improving its relations with the Russian state and potentially regaining access to lucrative unexplored reserves.