By Bill Wilson
Business reporter, BBC News
"We less and less view each other's actions with suspicion."
The joint venture has been increasingly troubled in recent months
With these words in 2003, the then BP chief executive Lord Brown attempted to assuage the fears of those who felt the firm could be facing rocky times ahead by setting up a joint venture in Russia.
But, despite misgivings about the commercial culture in an increasingly autocratic Russia, the lure of doing business in a country which pumped out 8m barrels of oil a day was too great for BP to ignore.
In August 2003, it completed a $6bn (Ł3.6bn) deal to set up a 50/50 joint venture with TNK, the third largest oil company in Russia.
But, if merging BP's and TNK's business cultures was "an uphill struggle" back then, what has happened this year has put those early difficulties in the shade.
This year TNK-BP has been kept on the back foot by a series of lawsuits, visa rows, industrial spying claims, staff contract investigations, as well as arguments over investment and on the future of chief executive Robert Dudley.
Many of the challenges have come from the billionaires who make up the Russian shareholding side of TNK-BP. AAR is controlled by Mikhail Fridman, Viktor Vekselberg, German Khan and Leonid Blavatnik.
Barely a day now goes by without some new development.
In the latest twist BP has said Robert Dudley, the chief executive of TNK-BP had temporarily left Russia to run the company from outside the country.
The under-fire boss was one of a number of staff who had been having visa problems.
"Mr Dudley will continue as group CEO, and as president and chairman of the management board of TNK-BP management and has all requisite authority to continue to run the company," the statement said.
"The company will continue to operate and trade as normal," it added.
BP also says it is to appeal against a Siberian court ruling that company contracts allowing its technical staff to work on the joint venture as "secondees" were invalid.
Meanwhile, the Russian billionaire consortium, known as AAR, is seemingly intensifying its move for control of the joint venture.
Media reports say these oligarchs have sent Mr Dudley a letter, claiming he has approved investment in TNK-BP in the face of their opposition. They are subsequently said to be threatening to seek damages.
The Russian state has restricted itself to a brief comment from Russia's finance minister Alexei Kudrin saying the dispute should "end in a civilised way".
Some have accused the government of tacitly supporting AAR in its moves to make life awkward enough for BP that it eventually considers leaving the country.
Russia's economic growth has been based largely on its huge reserves of gas and oil, and in recent years the Kremlin has shown itself adept at holding on to those assets.
BP relies on TNK-BP for more than 20% of the oil and gas it produces
Yukos, once Russia's biggest oil company, was brought to its knees through huge back-tax claims and eventually bankrupted.
Its assets are now largely owned by state oil firm Rosneft.
And in 2006, Shell lost control of key interests in its Russian Sakhalin-2 oil and gas project to Russian energy giant Gazprom, following intense political pressure from the Kremlin.
As a recent credit report from Standard & Poor's on TNK-BP observed: "Relative weaknesses include the current shareholder disputes and uncertainty on shareholder developments and their impact, together with general Russian country risks - including resource nationalism, increased risk of environmental breaches and licence revocation, and back-tax claims."
At this stage it is not possible to say that BP will eventually be forced out of its partnership, but the pressure continues.
On Wednesday a Siberian court ruled in favour of brokerage ZAO Tetlis - a minor stakeholder in TNK-BP Holding, claiming the fees TNK-BP has paid for the use of BP's specialist "secondees" amounted to an illegal dividend for BP.
BP denies this and says the staff were employed on equal terms with other TNK-BP staff.
However, earlier this week, BP withdrew the last 60 of its 148 employees it had seconded to TNK-BP. The other 88 had already been diverted to other BP projects.
TNK-BP's offices were raided in March, and this was followed by legal challenges to the status of these BP employees seconded to the joint venture.
Earlier this week BP said staff had been unable to provide their services to TNK-BP since work visa complications prevented them from doing so in March.
'Agreed spending plan'
Meanwhile, the pressure on Mr Dudley continues, with reports that AAR - which is also said to want higher dividend payments - claims he sanctioned expenditure at TNK-BP above an agreed limit.
The Russian investors have previously accused him of acting in BP interests alone, and last month called unsuccessfully for his dismissal.
Russian shareholders have so far not had Robert Dudley removed
But a BP spokesman said: "We are absolutely confident Robert Dudley will be remaining, and will continue to act in the interest of all shareholders.
"And we are confident TNK-BP's capital spending plan is being carried out according to a plan agreed by the TNK-BP board."
However, Mr Dudley - who has a work permit until July 2009 - has had ongoing visa problems of his own.
His visa run out on 19 July, but he was granted a transit visa valid until 29 July.
He has now left the country and BP said it "sympathised with Mr Dudley's view that the continued harrasment orchestrated by AAR shareholders" was preventing him serving TNK-BP properly.
A dispute over whether he has a valid employment contract could have prevented him having his visa renewed.
The Russian shareholders claim the contract expired late last year and had not been officially renewed, but BP says the contract is valid.
'Successful oil company'
After the announcement to remove the secondees from Russia earlier this week, Lamar Mckay, BP's executive vice president said: “We are taking this action reluctantly.
"These technical experts have played a huge part in making TNK-BP one of Russia's most successful oil companies in the past few years."
He said since it was founded in August 2003 the company's oil output had grown by an annual average of 5.8%, and that it had also paid $70bn of taxes and duties, as well as $20bn in dividends.
BP relies on TNK-BP for more than 20% of the oil and gas it produces, and will be hoping that it can fend off the increasing and sustained pressure on the joint venture.
Its Russian partners seem to have other ideas.