BP chief executive Tony Hayward was heckled by a protester as he attempted to apologise for the Gulf of Mexico oil disaster today.
The woman - with what appeared to be oil smeared on her face and hands - shouted "You need to go to jail" as Mr Hayward tried to address a Congressional committee hearing.
He had earlier sat silently as a succession of US politicians lambasted BP for what they alleged to be "astonishing" corporate complacency.
When Mr Hayward eventually read his evidence, he said he was "personally devastated" by the explosion which killed 11 workers on the Deepwater Horizon rig and the resulting oil spill.
Mr Hayward went on: "I understand how serious the situation is - it is a tragedy."
BP would foot the entire clean-up bill, the chief executive said.
"I give my pledge, as the leader of BP, that we will not rest until we make this right. We are a strong company and no resources will be spared."
He said it was still "too early to say" what caused the incident.
But he added: "I'm here today because I have a responsibility to the American people to do my best to explain what BP has done, is doing and will do in the future to respond to this terrible accident.
"First, we are doing everything we can to secure the well and in the meantime contain the flow of oil."
Some of the work should be complete in August, he said.
"Simultaneously, we have been working on parallel strategies to minimise or stop the flow of oil.
"While not all of them have been met with success, it appears the containment effort is now containing about 20,000 barrels a day."
By mid-July this should rise to between 60,000 and 80,000 barrels a day, he said.
"Second, I have been clear that we will pay all necessary costs."
He insisted that the company would pay "all legitimate claims for losses and damage", adding: "These are not just words. We have already paid out more than 95 million dollars (£64 million)."
The under-fire BP boss had earlier endured more than an hour-and-a-half of strong criticism directed at both him and his company.
A succession of members of the House of Representatives' Committee on Energy and Commerce attacked the BP boss.
The hearing came a day after BP announced a 20 billion dollar (£13.5 billion) clean-up fund to compensate victims and the suspension of dividends to shareholders.
But it was not enough to abate the anger of US politicians.
Henry Waxman, Democrat chairman of the committee, accused Mr Hayward of not paying "even the slightest attention to the dangers" at Deepwater Horizon.
This was despite the oil firm's drilling engineer warning that it was a "nightmare" rig just days before the April 20 accident.
"BP's corporate complacency is astonishing," Mr Waxman added.
Pennsylvanian Congressman Mike Doyle accused BP of "bad judgment at best and criminal negligence at worst".
He described the 20 billion dollar clean-up fund as "just the tip of the iceberg".
There was, however, some criticism of President Barack Obama's administration for strong-arming BP into yesterday's announcement.
Republican representative Joe Barton said it amounted to a "20 billion dollar shakedown" by the White House.
Most committee members, however, were content to focus their criticism solely on BP.
Vermont representative Peter Welch reeled off a list of safety failings at the oil giant in the years leading up to the Deepwater Horizon blast.
"For 59 days, BP has told the American people that this was an aberration. It is not an aberration - for BP this is business as usual.
"It is deja vu again and again and again."
He wondered, given BP's failings, whether it was time for its chief executive to "submit his resignation".
Asked if he expected to remain BP's chief executive, Mr Hayward said: "At the moment I am focused on the response."
Pushed on his record as chief executive, Mr Hayward said: "Since becoming CEO of this company I have focused on safe, reliable operations."
It was pointed out that, over the last five years, 26 people have died and more than 170 have been injured at BP rigs.
"We are engaging in a systematic change at BP, we have begun to change the culture," Mr Hayward said.
Opening the questioning of Mr Hayward, Bart Stupak, chairman of the Oversight and Investigations Subcommittee, said: "Quite frankly, BP blew it. You cut corners to save money and time."
Mr Hayward said it was "too early" to reach conclusions over the cause of the disaster. "The investigation is ongoing," he said.
Mr Hayward again defended his approach to safety since becoming chief executive of BP in 2007.
"We have focused like a laser on safe and reliable operations - that is a fact," he said.
As the hearing became more confrontational, Mr Hayward was accused of ignoring warnings over safety risks.
He was also accused of "stone-walling" and "failing to co-operate" with the sub-committee.
Mr Waxman angrily told the BP chief executive: "I am just amazed at this testimony.
"You are not taking responsibility, you are kicking the can down the road and acting like you have nothing to do with this company."
Mr Hayward repeatedly replied "I was not involved in that decision" and "I'm afraid I can't recall" when asked about specifics concerning the construction and safety testing of Deepwater Horizon.
Prime Minister David Cameron, speaking in Brussels before returning to London from an EU summit, said BP was important for both the US and UK and urged "clarity and certainty" for the company from Washington to ensure its stability.
He went on: "What happened is clearly an environmental catastrophe and we have to do everything we can to help with the clean-up.
"BP is an important multinational company. It's important to the UK. It's also important, I would argue, to the US. About 40% of its shareholders are UK-based. I think 39% are US-based. It employs tens of thousands of people in the UK. It employs tens of thousands of people, many more, in the US.
"It's an important company and I want to see it as a strong and stable company."
Mr Cameron went on: "The sensible way to deal with these things is talking about these things, as President Obama and I did in a phone call last weekend.
"BP itself recognises that it has huge obligations and it will have to spend a huge amount of money to cap the leak, to pay for the clean-up and pay compensation where it is appropriate. All of those things it wants to do and, of course, it should do.
"I know what BP also wants is some form of clarity and certainty about the future, so it can be a strong and stable company. Of course, as the British Prime Minister, I'd like to see that happen."Reuse content