Interior Secretary Ken Salazar concedes the government failed to hold the oil industry accountable and ensure safety in offshore oil drilling.

He promises to give "more tools, more resources, more independence and greater authority" to the Minerals Management Service, which regulates drilling in the Gulf of Mexico.

Salazar on Tuesday was making his first appearance before Congress since the April 20 oil spill. He says in prepared testimony that oil companies have opposed efforts to change "the culture of doing business" at the agency.

But Salazar tells the Senate Energy and Natural Resources Committee, "We have not and we will not back down on our reform agenda."