BP says it has reached a significant milestone in efforts to plug a leaking well in the Gulf of Mexico for good.
The company says heavy drilling mud that has been pumped from the surface to stem the flow of oil, is now controlling its pressure. The next step is to pump in cement behind the mud as a seal.
The White House says three-quarters of the oil now seems to have gone.
Energy adviser Carol Browner says the oil has either been captured, burned off, evaporated or broken down by nature.
About 4.95 million barrels of crude oil are estimated to have leaked into the sea.
The well ruptured after an explosion and fire on the Deepwater Explorer drilling rig on 20 April, killing 11 workers. The leak was finally stopped on 15 July.
Last week, BP reported a record loss of $US17 billion, having set aside $US32 billion to cover the costs of the disaster.
