An administration official familiar with the spill oversight, however, told The Associated Press that a seep and possible methane were found near the busted oil well. The official spoke on condition of anonymity Sunday because an announcement about the next steps had not been made yet.
The concern all along -- since pressure readings on the cap weren't as high as expected -- was a leak elsewhere in the wellbore, meaning the cap may have to be reopened to prevent the environmental disaster from becoming even worse and harder to fix.
The official, who would not clarify what is seeping near the well, also said BP is not complying with the government's demand for more monitoring.
Retired Coast Guard Adm. Thad Allen, the Obama administration's spill response chief, demanded BP provide results of further testing of the seabed by 9 p.m. EDT Sunday night.
"When seeps are detected, you are directed to marshal resources, quickly investigate, and report findings to the government in no more than four hours. I direct you to provide me a written procedure for opening the choke valve as quickly as possible without damaging the well should hydrocarbon seepage near the well head be confirmed," Allen said in a letter to BP Managing Director Bob Dudley.
When asked about the situation earlier Sunday before the letter was released, BP spokesman Mark Salt would only say that "we continue to work very closely with all government scientists on this."
Allen insisted Sunday that "nothing has changed" since Saturday, when he said oil would eventually be piped to surface ships. The government is overseeing BP's work to stop the leak, which ultimately is to be plugged using a relief well.
Allen decided to extend testing of the cap that had been scheduled to end Sunday, the official who spoke on condition of anonymity said. That means the oil will stay in the well for now as scientists continue run tests and monitor pressure readings. The official didn't say how long that would take.
Officials at the Department of Homeland Security referred questions to a statement issued by Allen; neither he nor BP officials could explain the apparent contradiction in plans.
Suttles' comments carved out an important piece of turf for BP: If Allen sticks with the containment plan and oil again pours forth into the Gulf, even briefly, it will be the government's doing, not BP's.
The company very much wants to avoid a repeat of the live underwater video that showed millions of gallons of oil spewing from the blown well for weeks.
"I can see why they're pushing for keeping the cap on and shut in until the relief well is in place," said Daniel Keeney, president of a Dallas-based public relations firm.
The government wants to eliminate any chance of making matters worse, while BP is loath to lose the momentum it gained the moment it finally halted the leak, Keeney said.
"They want to project being on the same team, but they have different end results that benefit each," he said.
Oil would have to be released under Allen's plan, which would ease concerns that the capped reservoir might force its way out through another route. Those concerns stem from pressure readings in the cap that have been lower than expected.
Scientists still aren't sure whether the pressure readings mean a leak elsewhere in the well bore, possibly deep down in bedrock, which could make the seabed unstable. Oil would be have to be released into the water to relieve pressure and allow crews to hook up the ships, BP and Allen have said.
So far, there have been no signs of a leak.
"We're not seeing any problems at this point with the shut-in," Suttles said at a Sunday morning briefing.
Allen said later Sunday that scientists and engineers would continue to evaluate and monitor the cap through acoustic, sonar and seismic readings.
They're looking to determine whether low pressure readings mean that more oil than expected poured into the Gulf of Mexico since the BP-leased Deepwater Horizon rig exploded April 20, killing 11 people and touching off one of America's worst environment crises.