BP rocked yet again after Barack Obama compares Gulf oil disaster to 9/11

• Artwork on a wall voices displeasure with both BP and President Obama. Picture: Getty

The shares were down 10 per cent at one stage – wiping more than 7 billion off the stock value of the firm – as nervous investors headed for the exit.

The latest setback for BP came amid reports that two US senators had written to the firm demanding it set aside $20 billion (13.5bn) in a special account to pay for damages and clean-up costs.

BP declined to comment on the letter and said it would not make a statement on dividend payments following yesterday's board meeting.

Meanwhile, President Barack Obama began a two-day visit to the Gulf Coast to view the damage from the massive slick and talk to those hit by the disaster.

Earlier, he said the ongoing oil spill would change the way the US thinks about energy forever – comparing the effect of the disaster on the environment to the way 9/11 shaped US security policy.

BP came under heavy fire from the US president last week for "nickel-and-diming" people who live near the spill, while planning big dividends for investors.

But yesterday he added that it had paid 26,500 claims totalling 42.3 million to local businesses.

"We are working to hold BP accountable for the damage to the lands and the livelihoods of the Gulf Coast, and we are taking strong precautions to make certain a spill like this never happens again," Mr Obama said.

The company's latest update said the cost of the spill had reached 1.1bn so far and its containment cap on the leaking well had collected around 127,000 barrels of oil.

But the firm's shares have now slumped by almost half since the crisis began two months ago when the Deepwater Horizon rig exploded and sank with the loss of 11 lives.

The latest tranche of dividend due in July is expected to be worth around 1.7bn, and BP has confirmed its directors would consider various options.

If the firm does decide to suspend the dividend, it would hit UK pension funds and investors in the US, who hold about 40 per cent of the company's shares.

Mr Obama has summoned BP's chairman, Carl-Henric Svanberg, to the White House tomorrow to explain what the company is doing to stop the flow of tens of thousands of barrels of oil and how it will compensate the thousands of people – including fishermen and oil workers – who have lost out as a result.

Meanwhile, under-fire chief executive Tony Hayward faces a stormy grilling in Congress on Thursday, which has the potential to reignite transatlantic tensions eased over the weekend in a call between Mr Obama and Prime Minister David Cameron.

During the call, the president assured Mr Cameron he had "no interest in undermining BP's value" – and the two leaders agreed BP should continue to work intensively to ensure that "all sensible and reasonable steps are taken as rapidly as practicable to deal with the consequences of this catastrophe".

BP's shares closed 9 per cent lower at 355.45p, despite a 0.7 per cent gain for the wider FTSE 100 Index.

David Jones, chief market strategist at IG Index, said it had been a "crushing" start to the week for the firm.

"With further news on whether the dividend is to be maintained not likely for at least a few more days, it would seem investors are losing their nerve," he warned.

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