World Bulletin / News Desk 

BP Plc will pay up to $18.7 billion in penalties to the U.S. government and five states to resolve nearly all claims from its deadly Gulf of Mexico oil spill five years ago in the largest corporate settlement in U.S. history.

The agreement adds to the $43.8 billion that BP had previously set aside for criminal and civil penalties and cleanup costs. The company said its total pre-tax charge for the spill now stands at $53.8 billion. 

The rig explosion on April 20, 2010, the worst offshore oil disaster in U.S. history, killed 11 workers and spewed millions of barrels of oil onto the shorelines of several states for nearly three months.

The agreement, which still needs to be approved by courts, covers Clean Water Act fines and natural resources damages, along with claims by Alabama, Florida, Louisiana, Mississippi and Texas as well as 400 local government entities.

"This is a realistic outcome which provides clarity and certainty for all parties," BP Chief Executive Officer Bob Dudley said in a statement. "For BP, this agreement will resolve the largest liabilities remaining from the tragic accident."

The settlement announced Thursday closes off those remaining liabilities.

"This agreement will not only restore the damage inflicted on our coastal resources by the Deepwater Horizon oil spill, it will also allow Louisiana to continue aggressively fighting coastal erosion," said Governor Bobby Jindal of Louisiana, the hardest hit state.

"Companies have been slightly hesitant to make a bid while this has been hanging over it, so I think it does clear the way for a potential bid," said Joe Rundle, head of trading at U.K.-based ETX Capital.

BP said the government and the states could jointly demand an acceleration of payments if the company were acquired.

"Now Gulf Coast restoration can begin in earnest. It's time to heal the wounds that BP tore in Gulf Coast ecosystems and communities," said David Yarnold, CEO of the National Audubon Society.