BP has forecast that the disaster will cost a total of about $32bn, after enduring a $16.9bn loss in the second quarter, the biggest quarterly loss in British corporate history.
The company is seeking to sell $30bn of assets over the next 18 months to help meet the clean-up bill.
'No oil leak'
BP confirmed this week that no oil is leaking into the Gulf following last week's successful effort to plug the well.
The success, almost four months after the catastrophic leak started, came after a procedure known as 'static kill’ was launched to stem the flow of oil.
That process involved filling the pipe with mud and cement from the top.
The oil spill followed an explosion at the Deepwater Horizon rig on April 20 that killed 11 workers.
Since then an estimated five million barrels of oil have poured into the Gulf.
The spill is the world's largest accidental release of oil, surpassing the 1979 Ixtoc well blowout in Mexico's Bay of Campeche that leaked almost three million barrels.
Since the leak was plugged, BP's shares have slightly increased after falling 22 per cent over the past three months.