BP on Wednesday sued the maker of the device that failed to stop last year's calamitous Gulf oil spill and the owner of the rig that exploded, alleging that negligence by both helped cause the disaster.

The British company said in papers filed in federal court in New Orleans that it is suing rig owner Transocean for at least $40 billion in damages, accusing it of causing last year's deadly blowout in the Gulf of Mexico that led to the worst offshore oil spill in US history. BP says every single safety system and device and well control procedure on the Deepwater Horizon rig failed. 

It also is suing Cameron International, which provided a blowout preventer with a faulty design, which caused an unreasonable amount of risk that harm would occur.

The lawsuits, filed on the first anniversary of the explosion that led to the spill, seeks damages to help BP pay for the tens of billions of dollars in liabilities it has incurred from the disaster.

Though BP has estimated its liabilities at $40.9 billion, it still could face tens of billions of dollars more in civil and criminal fines and penalties from the US government.

"The Deepwater Horizon BOP was unreasonably dangerous, and has caused and continues to cause harm, loss, injuries, and damages to BP (and others) stemming from the blowout of Macondo well, the resulting explosion and fire onboard the Deepwater Horizon, the efforts to regain control of the Macondo well, and the oil spill that ensued before control of the Macondo well could be regained," BP said in the lawsuit against Cameron.