AFP

WHEN your Moscow office is raided by Russia's security services, a court in Siberia imposes an injunction on your staff and your work permits are denied, you can tell you have upset someone. But who, and how? That is what BP, a British oil firm which owns 50% of TNK-BP, a joint venture with a Russian firm, has been trying to find out.

The firm has been under pressure from the Russian authorities before. The threat of losing its licence for the giant Kovykta field in East Siberia persuaded it to sell 63% to Gazprom, the state gas monopoly. Given the dire state of Russian-British relations and the state's distaste for foreign ownership of its oil reserves, it seemed natural to suspect the Kremlin when BP ran into visa problems in March. The arrest of a TNK-BP employee on espionage charges heightened such suspicions.

But this neat picture has just been dispelled by Robert Dudley, the boss of TNK-BP, who blames BP's recent troubles on its Russian partners. They are Mikhail Fridman, the head of Alfa Group, and his partners Viktor Vekselberg and Leonard Blavatnik, who are collectively known as the AlfaAccessRenova consortium. In an interview with Vedomosti, a Russian business daily, Mr Dudley said there were disagreements between TNK-BP's shareholders, and that managers had deliberately filed incorrect visa applications for 150 of TNK-BP's foreign staff.

Separately, an obscure Moscow brokerage, called Tetlis, filed a lawsuit in Siberia claiming that TNK-BP's payments to BP contractors amounted to extra dividends, and secured an injunction barring BP staff from TNK-BP. According to Tetlis's website, two of its three top managers used to work for Mr Fridman's Alfa Group.

The Russian shareholders want Mr Dudley out, and walked out of talks with Tony Hayward, the head of BP, after he refused to give in. On Thursday June 5th Mr Hayward arrived in Russia for more talks with shareholders and government officials. He used a speech at the annual general meeting of Rosneft, a state-controlled firm, to give warning that the country's success depends on the “consistent application of the rule of law”. He also met Igor Sechin, the deputy prime minister responsible for energy, among other officials, and was expected to meet Mr Fridman.

So what is behind the hostility? People close to BP say the Russian oligarchs are up to their old tricks again, and are trying to exploit Russia's weak institutions and take control.

Russian business practices can be (and often are) shockingly crude. But the Russian shareholders claim to have a genuine grievance. They say BP treats TNK-BP as a subsidiary, rather than an independent company run for the benefit of all shareholders. They say BP cares more about its oil reserves than costs or profits. TNK-BP provides 40% of BP's replacement reserves and 25% of its oil production. The Russians would like TNK-BP to expand abroad, but that would turn it into a rival to BP.

A recent memo from Mr Dudley, seen by The Economist, bars managers from discussing deals in countries blacklisted by America's state department, including Cuba, Iran and Syria. “TNK-BP is an independent Russian company and should be subject to Russian laws,” says Mr Fridman. Russian shareholders also object to TNK-BP's payment of hundreds of millions of dollars to BP contractors, citing a conflict of interest. “There is certainly room for cost cutting in TNK-BP,” says Ivan Mazalov, a fund manager at Prosperity Capital Management, a minority shareholder.

In any other country this would have been an ordinary shareholder dispute, but in Russia, politics always get in the way. The picture has been muddied by Gazprom, which has signalled its intention to buy out the Russian shareholders in TNK-BP and form its own partnership with the British firm. BP seems to like the idea and has engaged in negotiations.

Gazprom had also proposed an option for BP to buy back 25% of the Kovykta field in return for some valuable assets outside Russia. People close to BP say the deal is being held up by the Russian shareholders' reluctance to sell their stake in TNK-BP and the recent hostilities are simply a negotiating ploy. Given Gazprom's political power, they and many others assume that the Russian shareholders will have to sell.

Yet Gazprom, which has huge debts, does not have the free cash to buy them out. (TNK-BP could be worth up to $60 billion.) Mr Fridman, who also has powerful patrons in the Kremlin, says nobody has asked him about the sale of his stake—and even if they did, he would not sell. Navigating Russian politics when nobody knows who really runs the country is a futile task. The two sides would be better off sticking to business.