The massive oil leak in Gulf of Mexico has been temporarily halted with the help of thousands of barrels of mud being pumped into the ruptured well.
With criticism of the fuel giant at its peak as millions of gallons of crude continue to spill into the sea, engineers attempted a last-ditch clogging method known as top kill.
BP resumed pumping mud into the well to halt the leak after it was suspended to bring checks and changes to the procedure.
The technique will serve as a temporary block on the ruptured well until another well can be drilled and used to permanently seal it with cement.
BP estimates that the full top kill procedure could extend for another 24 to 48 hours.
Meanwhile, US geological survey director Marcia McNutt said the ruptured well has been leaking oil at an estimated rate of 12,000 to 19,000 barrels a day since the rig exploded then sank in April.
BP said the response costs have risen to about $930m.