The U.S. government is to set up an independent commission to investigate the Deepwater Horizon oil spill in the Gulf of Mexico.
Expert witnesses have given evidence to a Congress committee but lawmakers remain critical of government and industry attempts to mitigate the environmental and economic costs of the spill.
It comes as scientists say oil from the spill has been picked up by a powerful ocean current, which could carry it around Florida and up the east coast of the USA.
Analysis of European Space Agency images suggests the oil could reach coral reefs in the Florida Keys within six days.
Meanwhile, tests on tar balls washed up on beaches in the mouth of the Mississippi delta in the last few days have shown they came from the Deepwater Horizon spill.
Experts are bracing themselves for more.