BP has said it is ready to face the federal civil trial, due to start on 25 February, in the Deepwater Horizon Multi-District Litigation pending in the US District Court.

The proceeding will be the first of two phases the court has decided for the trial. The first phase will concentrate on the causes of the Deepwater Horizon accident, who should be held responsible and to what degree.

BP said in a press statement that it "will vigorously defend against gross negligence allegations".

BP Group General Counsel Rupert Bondy said: "We have always been open to settlements on reasonable terms, failing which we have always been prepared to defend our case at trial. Faced with demands that are excessive and not based on reality or the merits of the case, we are going to trial."

During the trial the court is expected to determine the legal and factual issues related to the case, and will also consider whether BP or any other party was grossly negligent.

"BP said in a press statement that it "will vigorously defend against gross negligence allegations"."

"Gross negligence is a very high bar that BP believes cannot be met in this case," Bondy added. "This was a tragic accident, resulting from multiple causes and involving multiple parties. We firmly believe we were not grossly negligent."

The second phase of the trial, which is expected to commence in September 2013, will address issues related to oil flow rate and quantification of barrels of oil spilled. BP has earlier said that the government’s public estimate of 4.9 million barrels of oil released is 20% exaggerated.

The company said it does not believe that the 810,000 barrels of oil that it has captured from the Macondo reservoir, without leaving it to enter the Gulf of Mexico waters, should also be considered in the court’s future determination of Clean Water Act penalties.

As per the Clean Water Act, civil penalties are calculated only on oil that has actually entered the environment and potentially caused harm, while the US Department of Justice has also said it has the same opinion with BP on this issue.

BP said that as per its analysis, around 3.1 million barrels should be the uppermost limit of the number of barrels spilled that should be used in calculating a Clean Water Act penalty.

The company’s assessment is on the basis that the 4.9 million barrels figure includes an over-estimate of at least 20% and that a further 810,000 barrels should be deducted from the volume that flowed from the reservoir.

"In determining the penalty, we believe the court should consider, among other things, the fact that BP immediately stepped up and acknowledged our role in the accident," Bondy added.

"We waived the statutory cap on liability, and to date, we’ve spent more than $23bn in response, clean-up and payments on claims by individuals, businesses and governments."

Image: Deepwater Horizon offshore drilling unit on fire.