"We are taking a hard look at ourselves, what we do and how we do it," he said. "What we learn will have implications for our ways of working, our strategy and our governance."
Svanberg said the company's priority was to stop the Gulf leak permanently and then to clean up miles of spoiled waters and beaches and compensate people whose livelihoods have been lost because of the accident.
But he added that the company was determined to restore value to shareholders, after a 35 percent, or $60 billion, drop in market value to around $116 billion since the explosion. Under U.S. political pressure, the company also axed dividends to shareholders this year.
The stock started out marginally higher on Tuesday, but dropped 3 percent to 404.2 pence in afternoon trade on the London Stock Exchange.
In New York, BP stock slumped about 2 percent to $37.87 after BP announced it would sell $30 billion in assets to help pay potential costs related to the spill.
Analysts said they were disappointed at how many assets BP was willing to sell, and its cost estimate was thought to be on the conservative side.
BP made its estimate on the assumption that it won't be deemed "grossly negligent" in its handling of the well. If it is, then BP won't be able to ask its partners to help pay for the cleanup, and federal fines will go up.
"The penalties are obviously going to be more than what they're saying," Oppenheimer & Co. analyst Fadel Gheit said.
Dudley, BP's managing director, was brought in to oversee the spill response after Hayward was vilified for a series of ill-timed moves, including saying that he would like his life back and attending a yacht race off the coast of England as Gulf residents struggled to cope with the spill.
Dudley spent some of his childhood in Mississippi and worked for 20 years at Amoco Corp., which merged with BP in 1998. He lost out to Hayward on the CEO slot three years ago.
"I don't particularly like talking about myself, but I think you will find I listen hard and carefully to people and have worked with restructuring organizations to achieve change," he said. "I did not seek out this job. I was asked to step into these shoes, and I firmly and deeply believe that BP is a company made up of great people and great businesses."
Dudley will be based in London and will hand over spill response coordination to Lamar McKay, the chairman and president of BP America.
He also downplayed speculation that BP might pull back from the Gulf once the flow of oil is stopped permanently, which could happen as soon as mid-August.
"There's no one thinking that way," he said.
Retired Coast Guard Adm. Thad Allen, the government's point man on the spill, said Tuesday the amount of effort devoted to stopping the oil and cleaning up the mess won't change with Dudley's appointment.
"That's not to say that leadership is not important," he said. "We work very closely together, and we've been very focused on response."
BP kicked off the revamp by announcing the sale of $30 billion in assets to streamline the company into a leaner, higher-quality business.
The company has already made a start with the $7 billion sale of gas assets in the United States, Canada and Egypt to Apache Corp.
Svanberg said the planned asset sales did not necessarily reflect a fear that spill costs could soar above the $32.2 billion set aside by the company. That charge includes the $20 billion compensation fund the company set up following pressure from President Barack Obama as well as costs to date of $2.9 billion.
Hayward, who will stay on BP's board until Nov. 30, said the company had reached a "significant milestone" with the temporary capping of the leaking well, which stopped oil from spewing nearly two weeks ago. Before that, anywhere from 94 million to 184 million gallons had gushed into the Gulf.