US President Barack Obama has described a sprawling oil slick in the Gulf of Mexico as a "potentially unprecedented" environmental disaster.

Speaking in Louisiana, Mr Obama said his government would do whatever it takes to clean up the oil, adding that BP was responsible and must pay.

He said the focus was now on preventing any further damage to the Gulf coast.

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.

BP is responsible for this leak, BP will be paying the bill  Barack Obama Strong winds drive slick onshore Your stories of the oil spill In pictures: Oil spill clean-up

The BP-operated Deepwater Horizon rig sank on 22 April, two days after a huge explosion that killed 11 workers.

Louisiana Governor Bobby Jindal has warned the spill threatens the way of life in his state.

Mr Obama flew to Louisiana on Sunday to see for himself the damage.

Speaking in the town of Venice, he said: "We're dealing with a massive and potentially unprecedented environmental disaster.

"The oil that is still leaking from the well could seriously damage the economy and the environment of our Gulf states.

"And it could extend for a long time. It could jeopardise the livelihoods of thousands of Americans who call this place home."

Following the explosion of a BP-operated rig, an oil slick has begun washing up on the Louisiana coast and is threatening three other states.

Up to 5,000 barrels of oil a day are gushing into the sea. The oil slick is moving towards the coast line and communities are waiting to find out how it will affect them.

BBC News website readers discuss their concerns as they wait for news.

Saturday 1 May:

I own and operate boat tours of the Pascagoula River swamp and marsh. This oil spill has given me the most sickening feeling. We are just waiting for the thing to hit and wondering how it will affect us.

My business already seems to have been affected. I usually have several phone calls a day but none so far. I have nothing booked for the weekend, which is unusual.

If it's the magnitude they're predicting, it could be the end of life as we know it here on the beautiful Mississippi Gulf Coast, at least until the spill is completely cleaned up. It breaks my heart to think of all the marine life and birds that will no doubt be affected by this disaster.

The mutation may have helped mammoths survive in the ice Age

Mammoths had a form of "anti-freeze" blood to keep their bodies supplied with oxygen at freezing temperatures.

Nature Genetics reports that scientists "resurrected" a woolly mammoth blood protein to come to their finding.

This protein, known as haemoglobin, is found in red blood cells, where it binds to and carries oxygen.

The team found that mammoths possessed a genetic adaptation allowing their haemoglobin to release oxygen into the body even at low temperatures.

The ability of haemoglobin to release oxygen to the body's tissues is generally inhibited by the cold.

The resulting haemoglobin molecules are no different than 'going back in time' and taking a blood sample from a real mammoth  Kevin Campbell University of Manitoba

The researchers sequenced haemoglobin genes from the DNA of three Siberian mammoths, tens of thousands of years old, which were preserved in the permafrost.

The mammoth DNA sequences were converted into RNA (a molecule similar to DNA which is central to the production of proteins) and inserted into E. coli bacteria.

The bacteria faithfully manufactured the mammoth protein.

"The resulting haemoglobin molecules are no different than 'going back in time' and taking a blood sample from a real mammoth," said co-author Kevin Campbell, from the University of Manitoba in Canada.

Scientists then tested the "revived" mammoth proteins and found three distinctive changes in the haemoglobin sequence allowed mammoth blood to deliver oxygen to cells even at very low temperatures.

More than 2m bees were stolen last year, says Japan's apiary association

Japanese bee-keepers have been warned to be on their guard, following a spate of hive thefts.

The price of honeybees has doubled in recent years after a ban on imports. Police suspect a gang of specialist thieves is stealing honeybees to order.

In central Shizuoka prefecture, eight hives of 60,000 bees were taken in a single night from five separate farms.

The area is well known for strawberry growing and farmers need honeybees to propagate their crops.

The insects have been in short supply in Japan after imports were banned for several years to try to prevent the spread of parasites.

The price of a swarm has doubled to more than $400 (£260).

The Japan Beekeepers and Honey Association says more than two million of the insects were stolen in 2009, and thefts are becoming more frequent.

The organisation has urged its members to be alert, but has admitted it is difficult to protect hives around the clock on remote farms.