BP has asked a US court to reconsider its ruling of “gross negligence” over a 2010 oil spill in the Gulf of Mexico, which boosted its potential fines to around $18bn (£11.1bn).
BP said that Judge Barbier’s ruling in Louisiana was based on evidence he had said he would not consider in court.
For this reason, the oil company said the ruling should either be amended or there should be a new trial.
The incident killed 11 workers and was the worst offshore spill in US history.
The company has already set aside more than $42bn to cover the total cost of the accident.
BP said in a statement: “Through its motion, BP has asked the District Court to amend its September 4 Order or, in the alternative, to grant a new trial because the Court’s findings and conclusions are based substantially on expert witness opinions that the Court appropriately and expressly excluded from evidence at trial.
“Because those opinions were excluded by the Court, they cannot support key aspects of the Court’s findings, which should therefore be set aside.
“… the Court should order a new trial to permit BP to explore the lack of basis for the witness’s opinion.”
Judge Barbier had ruled that BP should shoulder 67% of the blame for the spill, with drilling rig owner Transocean responsible for 30% and cement firm Halliburton responsible for 3%.
He ruled that BP would be “subject to enhanced civil penalties” due to its “gross negligence” and “wilful misconduct”.