"We will fulfill the promises we've made to the gulf states and the federal government," Dudley said Tuesday at a briefing in London. "Meeting our commitments in the gulf is critical for BP's long-term success … Taking over this role, I will not reduce my commitment in the region."
He added that BP intends to restore its position in the United States and in the gulf. "We are certainly not intending to exit and shrink dramatically in the United States."
Dudley, 54, will take over from Tony Hayward, who announced Tuesday that he would step down in October.
"Today is a very sad day for me," Hayward said. "I spent my entire professional career at BP. I love the company and everything it stands for."
"It's clear that this tragedy will leave BP a changed company," he added. "To move forward, particularly in the United States, it should do so under new leadership."
The management change was widely expected -- it follows severe criticism of Hayward's crisis management in response to the April 20 Deepwater Horizon explosion that killed 11 workers and caused tens of millions of gallons of crude to pour into the gulf.
In a large BP campaign shortly after the spill, Hayward said in a commercial he wanted his "life back," angering Gulf Coast residents who don't think theirs will ever be the same.
The leak is capped but several previous attempts to seal it failed. Moreover, environmental groups have accused BP of purposefully downplaying the amount of oil that has been gushing into the gulf, with Hayward taking the brunt of public anger.
"I became as the face of BP the lightning rod for the very understandable anger and frustration among a very broad cross-section of the U.S. public," he said.
BP also suffered financially, with the company Tuesday reporting a record second-quarter loss of $17 billion, compared with a $4.4 billion profit in the period a year ago. The losses come as BP said it set $32.2 billion to deal with follow-up costs linked to the spill and could sell as much as $30 billion in assets, including parts in the United States.
Dudley, who grew up in Mississippi and currently runs BP's cleanup operation in the gulf, takes over the difficult task of returning BP to a profit-making enterprise after it lost some 35 percent of its net value since the April 20 explosion.
An experienced oil executive who joined BP in 1998 from Amoco when the two companies merged, the 54-year-old until 2008 served as the head of BP's Russian joint venture, TNK-BP.
Dudley will try to increase BP's reputation in the United States -- crucial for that will be how BP handles the post-spill response during the next months and how it operates in the future.
"We will work and embed tighter and deeper reviews on our safety practices," when drilling for oil, Dudley vowed. "We will learn many things from this tragic accident."
2014: The Year in Music [PHOTOS]