BP ratcheted up the rhetoric around multi-billion dollar claims from the Gulf oil spill by warning it would "vigorously" contest lawsuits over one of the world's worst environmental disasters.

While reiterating BP's "bias for settling" at hearings scheduled later this month, CEO Bob Dudley said he would only do so "on fair and reasonable terms."

As he unveiled higher fourth quarter profit on Tuesday and a rise in the dividend, which he said showed BP was putting the spill behind it, Dudley acknowledged the lawsuits were the biggest uncertainty facing the British oil major.