Marine scientists have discovered a massive new plume of what they believe to be oil deep beneath the Gulf of Mexico, stretching 22 miles (35km) from the leaking wellhead north-east towards Mobile Bay, Alabama.

Around one fifth of the oil gushing into the Gulf of Mexico from the rig disaster is now being collected by a bypass pipe, BP said tonight.

BP engineers finally succeeded in keeping some of the oil gushing from a blown well out of the Gulf of Mexico, hooking up a mile-long tube to funnel it into a tanker after more than three weeks of failures.