BP: The cap fits, but 20,000 barrels escape every day

Deepwater Horizon is spewing oil at about 40,000 barrels per day according to a new US government estimate - eight times the 5000-barrel figure that stood for most of May.

To deal with the extra flow, BP will begin to change the hoses that were previously used for the "top kill" effort into another riser system, bringing more oil to the surface.

The hoses could bring 10,000 barrels of oil up to a surface rig, but because the rig has no storage capacity, the oil will be burned off along with the natural gas.