BP boss Tony Hayward said on Thursday the British energy company "will not rest" until the Gulf of Mexico oil spill has been cleaned up, vowing to learn the lessons of such a "terrible event".
"Right now, it's simply too early to say what caused the incident. There is still extensive work to do. A full answer must await the outcome of multiple investigations, including the marine report," Hayward told US lawmakers.
"I know that only actions and results, not mere words ultimately can give you the confidence you seek. I give my pledge as the leader of BP that we will not rest until we make this right."
Answering concerns BP might struggle to meet the multi-bilion-dollar costs of cleaning up America's worst environmental disaster, Hayward said: "We're a strong company and no resources will be spared.
"We and the entire industry will learn from this terrible event and emerge stronger, smarter and safer."