BP and its partners on the...Deepwater Horizon oil rig face fines of up to $45m after receiving formal notice of a series of safety violations leading up to the Gulf of Mexico disaster. In a first step of a long legal battle, the interior department said BP, rig operator Transocean and contractor Halliburton between them broke 15 rules governing offshore drilling ahead of the 20 April 2010 explosion...[The] notices mark the first time the US government has gone after contractors – in this case Transocean and Halliburton – in addition to oil companies. The tactic could influence lawsuits between BP and its partners over their responsiblility...The companies have 60 days to appeal against the sanctions. Transocean said it would appeal. All three companies are pursuing lawsuits against one another and BP said in a statement that the notices showed its partners were partly to blame. "We continue to encourage other parties, including Transocean and Halliburton, to acknowledge their responsibilities in the accident."