White House Press Secretary Robert Gibbs spent much of today's press briefing rebutting recent criticism of White House efforts during the BP oil spill.

"Our response attacked the oil spill in an unprecedented way. It was the largest environmental disaster that we have ever faced. And we attacked it with the largest federal response."

A staff working paper from the National Commission on the BP Deepwater Horizon Oil Spill and Offshore drilling suggests that during the early days of the crisis, the White House may have sat on a "worst case" scenario estimate of oil flowing into the Gulf of Mexico.

"No information was altered. No information was withheld," said Gibbs.

The paper also claims that in late April or early May, the National Oceanic and Atmospheric Administration wanted to make public long-term, worst-case discharge models from BP's well and that the White House Office of Management and Budget (OMB) denied that request.

When asked directly about that allegation Mr. Gibbs said, "OMB sent the report back to NOAA to include that in the 500 different modeling analysis that were done on shoreline impact... The worst- case scenario was oil off the coast of what looks probably the Hilton Head/Charleston area in South Carolina, which, is, as you know, several hundred miles -- maybe a thousand or so miles from where the oil actually did get to, because the response prevented it from spreading."

The commission will be presenting a final report to the White House in January.

Initially the White House and BP estimated that the amount of oil gushing from the well was about 5,000 barrels per day, that turned out to be about one tenth of what was actually gushing out of the blown well head.

In August, the White House put out an "oil budget," which concluded about 75 percent of the oil was already gone, having been skimmed, burned, evaporated or dissolved. The staff paper specifically cited comments made by White House energy adviser Carol Browner on August 4 when she said, "The vast majority of the oil is gone."

"I think it is fair to say that Carol probably did hundreds of hours of interviews, and may have misspoke once, which is a pretty darn good track record and one that -- one that we made sure was accurate, certainly just a... few hours later," said Gibbs.

Jake Gibson is a producer working at the Fox News Washington bureau who covers politics, law enforcement and intelligence issues.