TNK-BP’s beleaguered chief executive has said a battle between BP and its Russian partners threatens to tear the oil venture apart after 16 of the company’s senior Russian managers rebelled by filing suit against him for discrimination.

Robert Dudley said on Thursday the lawsuit was a cynical “attack at the heart of the company” engineered by BP’s Russian billionaire partners in the 50:50 oil venture to split the company along nationalistic lines.