A giant oil slick from a deadly offshore drilling rig explosion could hit the fragile US Gulf Coast shoreline by Saturday.
The leak has a circumference of about 600 miles which is slightly bigger than the American state of West Virginia.
"The wind will nudge the oil slick more to the north-northwest," said Dan Kottlowski, senior meteorologist at AccuWeather. "It might make it onshore over the southeast Louisiana coast first, and later threaten beaches in Mississippi, Alabama and Florida," Kottlowski said.
The Coast Guard is using eight underwater robots to try to activate a cutoff valve on the ocean floor to stop the oil flow.
The leak may also be set alight where it is bubbling to the surface above the well to try to stop the spread.
The Swiss-based Transocean Ltd's Deepwater Horizon sank on April 22, two days after it exploded and caught fire.
The White House and Congress have launched separate probes in the worst offshore incident in nearly a decade.
The infamous Exxon Valdez disaster spilled about 11 million gallons of oil into the Prince William Sound in Alaska, when it ran aground in 1989.
