The US government is continuing to put pressure on BP, the British energy giant, to take responsibility for the fallout from its massive oil spill in the Gulf of Mexico.
Eric Holder, the US attorney-general, said he would take the necessary steps to ensure that the American people were not left paying for the cleanup and damages stemming from the April disaster and that BP will bear that cost.
"I can make this pledge to the American people that the American people will not pay a dime for the cleanup of the Gulf region and that BP will be held responsible for all the damages that have occurred," Holder told a news conference on Thursday.
"We will take the necessary steps to make sure that that occurs."
Holder declined to comment when asked whether the administration would seek an injunction against BP from paying its dividend to stockholders.
The White House said on Thursday that Barack Obama, the US president, and senior officials from his administration would meet Carl-Henric Svanberg, the chairman of BP, on Wednesday.
Speaker Nancy Pelosi, leader of the House of Representatives, said on Thursday that "every taxpayer in America must know that BP will be held accountable for what is owed".
Mitch McConnell, the Senate Republican leader, agreed BP has to "clean up the spill," but he said Democratic politicians should not use the tragedy to try to build support for an energy bill.
Asked if BP should cut its dividends to shareholders, Pelosi said: "I think it's appropriate for BP to be paying businesses in the Gulf.
"They have a responsibility under the law to pay these damages. They made $17bn last year. Maybe people who receive dividends have deeper pockets."
BP, which said last week it had "plenty of" cash to deal with the problem, has so far spent about $1.43bn on compensation and attempting to stop the leak.
Shares in BP closed down six per cent in London having earlier dropped by twelve per cent, its lowest level since 1997.
The company's shares price has now fallen by almost half, equal to about $70bn, since the Deepwater Horizon oil rig that it operated sank on April 22.
The oil spill has led to bitter recriminations between the US and the UK, where BP originated.
Following criticism of the company from Obama on the handling of the spill, Boris Johnson, the mayor of London, said that "anti-British rhetoric" was becoming increasingly common.
"I do think there's something slightly worrying about the anti-British rhetoric that seems to be permeating from America," Johnson told BBC radio.
"I would like to see a bit of cool heads rather than endlessly buck-passing and name-calling.
"When you consider the huge exposure of British pension funds to BP it starts to become a matter of national concern if a great British company is being continually beaten up on the airwaves.
"It was an accident that took place and BP is paying a very, very heavy price indeed."
Speaking publicly about the crisis for the first time on Thursday, David Cameron, the British prime minister, offered to help deal with the oil spill, saying he would take it up with Obama when he speaks to him by phone at the weekend.
"This is an environmental catastrophe," Cameron told reporters during a visit to Afghanistan.
"BP needs to do everything it can to deal with the situation and the UK government stands ready to help.
"I completely understand the US government's frustration. The most important thing is to try to mitigate the effects and get to grips with the problem.
"It's something I will discuss with the American president when we next talk."
BP has already been given a 72-hour deadline from Tuesday by the US government to produce improved plans on containing the giant spill.
The current procedure, which began on Saturday, involves a cap placed over the leak that gathers the oil, allowing it to be siphoned up via a pipe to a container ship.
By the most conservative estimate, 26 million litres of crude have spilled into the Gulf - though US officials say the actual tally could be much higher - since the crisis began when its offshore drilling rig exploded, killing 11 workers.
The oil spill has begun fouling the US coastline, coating birds and other wildlife, and severely affecting the fishing industry.