US President Barack Obama has told BP it will pay the bill for the clean up following the massive oil spill in the Gulf of Mexico

The statement came as Mr Obama described the sprawling oil slick in the Gulf of Mexico as a "potentially unprecedented" environmental disaster.

Mr Obama flew to Louisiana on Sunday to see the damage for himself. Speaking in the town of Venice, he warned: "BP is responsible for this leak. BP will be paying the bill."

The president said the slick was now nine miles (14km) off the coast of south-eastern Louisiana.

"We're dealing with a massive and potentially unprecedented environmental disaster" the President said.

"The oil that is still leaking from the well could seriously damage the economy and the environment of our Gulf states. It could jeopardise the livelihoods of thousands of Americans who call this place home."

BP says it will be at least a week before temporary measures to stem the leak are in place. But it could take up to three months to drill relief wells that could fully contain the spillage, Interior Secretary Ken Salazar warned on Sunday.