Engineers searched for ways to capture more oil flowing from a ruptured well in the Gulf of Mexico Sunday after energy giant BP said a cap was currently catching around 10,000 barrels a day.
As significant amounts of oil continued to escape into the sea, BP's chief executive Tony Hayward told the BBC, "As we speak, the containment cap is producing around 10,000 barrels of oil a day to the surface".
Earlier accounts put the amount of captured oil at 6,000 barrels a day.
Hayward added that he hoped that another containment system, due to be installed next weekend would help contain "the vast majority" of the leaking oil, but did not offer a specific figure.
While encouraging, the new figure was dwarfed by estimates that up to 19,000 barrels a day could be spewing from the leaking well.
The latest containment effort involves a cap placed over the leak that gathers the oil, allowing it to be siphoned up via a pipe to a container ship.
It is a modified version of an effort tried earlier in BP's six-week effort to stem the crude gushing from a ruptured underwater pipe after the Deepwater Horizon rig it leased exploded before sinking into the sea on April 22.
The earlier attempt failed because cold temperatures and high pressure at the leak site caused the oil to form a sludge that could not be siphoned.
The cap has been redesigned with valves that can be slowly shut down to help prevent the build-up of gas hydrates -- similar to ice crystals -- that doomed the first attempt.
However, experts said that the ultimate solution relies on drilling a relief well that will help insert heavy mud and cement in the leaking well and thus plug it.
BP is drilling two of them and estimates that they will be completed only in August.
During the night, all was not smooth sailing with the oil collection. "The flow of oil and gas to the Enterprise was shut down for three hours overnight," said Coast Guard spokesman First Class Petty Officer Zach Zubricki.
News of any successful effort to contain the disastrous spill will be welcomed by the four states so far affected by what is now the worst environmental disaster in US history.
On Saturday, US President Barack Obama pledged in his weekly radio address to use "every resource" to help those affected.
"We will continue to leverage every resource at our disposal to protect coastlines, to clean up the oil, to hold BP and other companies accountable for damages," he said.
An estimated 20 million gallons of crude has poured into the Gulf since the Deepwater Horizon sank April 22, 50 miles (80 kilometers) off Louisiana.
Eleven workers were killed in the blast, and Obama will meet their families in a White House ceremony next week.
Citing new government and BP documents and testimony by witnesses, The New York Times reported Sunday that a hodgepodge of oversight agencies granted rig operators exceptions to rules, allowed risks to accumulate and made the disaster more likely.
The president said the spill had "upended whole communities," and local residents were angry not just about lost income, but because of "the wrenching recognition that this time their lives may never be the same."
The scale of the disaster forced Obama to postpone a trip to Australia and Indonesia for the second time, as images of seabirds writhing in oil along the Louisiana coast blanketed US television networks and the front pages of newspapers, underscoring the rising environmental toll.
Spreading in oily ribbons, the slick is now threatening Alabama, Mississippi and Florida after contaminating more than 125 miles (200 kilometers) of Louisiana coastline.
Amid criticism over his handling of the crisis, Hayward has announced the formation of a team to work with locals and officials in the aftermath of the clean-up.
The team will be led by one of the oil giant's managing directors, Bob Dudley, a US citizen, and was seen as a sign that the clean-up and looming legal battles will likely last for years.
BP said Saturday it had paid out 46 million dollars in more than 17,000 claims checks since the disaster began and expected to pay the same amount in June,
"It'll be 84 million plus... at least what it was in May if not more," BP's lead claims coordinator Darryl Willis told reporters in a conference call from Orange Beach, Alabama.
Explore further: Huge tract of Australia in 'biggest ever drought'