American president Barack Obama has warned that the 'massive' oil spill in the Gulf of Mexico could be an environmental disaster like no other.
Speaking near the spill in Louisiana, he said the US government would do whatever it takes to clean up the oil.
But he said oil company BP was responsible for the spill and should pay for the clean up.
Oil has been gushing into the sea since a BP-operated oil rig exploded and sank off the coast of Louisiana on 20 April.
Eleven workers were killed in the explosion on the Deepwater Horizon rig.
The head of BP said the company hoped to lower a dome over the leaking well to try and stop the oil spill.
But officials are worried it could take up to three months to contain the spillage, which is now 14km off the Louisiana coast.
A Northern Gannet bird covered in oil is treated in Louisiana
Oil is pouring into the ocean at a rate of 5,000 barrels a day.
There are fears it could affect fishing in the area and endanger local wildlife including sea birds and turtles.