Oil leaking from a ruptured well pipe in the Gulf of Mexico washed ashore in two new locations on Saturday, the Coast Guard said, as the latest attempt to contain the spill faltered.

Efforts to siphon leaking oil via an "insertion tube" up to a container vessel continued a day after US President Barack Obama blasted oil companies for seeking to shift blame for a growing oil slick threatening environmental disaster.

Petty Officer Erik Swanson told AFP Saturday that oil from a riser pipe that ruptured after the collapse of the Deepwater Horizon rig had been discovered in two new locations -- Whiskey Island, Louisiana and Long Beach, Mississippi.

"We sent crews to assess what type of oil, and we determined it's 'soft patties' on Whiskey Island and 'tarballs' on Long Beach," he said.

Tarballs are small globs of oil, while soft patties are roughly six inches in diameter and more than a centimeter thick, he said.

The appearance of oil in new locations is a sign of the urgency of efforts to contain the spill, which experts warn may be growing more than ten times faster than previous Coast Guard estimates of 5,000 barrels (210,000 gallons) a day.

Scientists who analyzed the flow of oil in a video of the underwater leak fear the rate may be closer to 70,000 barrels (2.9 million gallons) a day.

The findings suggest the spill has already eclipsed the 1989 Exxon Valdez spill, which was the worst environmental disaster in US history.

BP disputes the figures, with Robert Dudley, BP's executive vice president for the Americas, telling CNN that "70,000 barrels a day isn't anywhere I think within the realm of possibility."

On Friday, a visibly angry Obama chastised British Petroleum, Transocean and Halliburton -- the firms that leased, owned and worked on the rig -- for seeking to shirk responsibility for the disaster.

He said top company officials had created a "ridiculous spectacle" in testimony before Congress and warned he would "not tolerate more finger pointing or irresponsibility."

BP, which leased the ill-fated Deepwater rig from Transocean, has pledged to pay for the costs of containing, capping and cleaning up the oil spill, and to compensate any "legitimate" claims stemming from the leak.

But multiple efforts over the last three weeks to stop the leak, or even to slow the flow of oil, have failed, and the latest attempt Saturday was proving more difficult than expected.

BP crews using remote-controlled submarines struggled to place an "insertion tube" into the leaking riser a mile (1.6 kilometers) down on the seabed.

Once inserted, the tube should be able to funnel the leaking oil up to a container vessel on the ocean surface, thought the method is untested.

"We were hoping it was going to be operational last night," BP spokesman John Crabtree said, acknowledging that the process was proving more complicated than expected.

It was unclear why engineers had failed to connect the tube, and how long they would keep trying before turning to alternative methods.

BP has already deployed to the seabed a so-called "top hat" container, which is attached to a siphon tube and could be lowered over the leak to collect and then funnel away the oil.

The method has been tried once before, but low temperatures and high pressure caused the oil to form sludge that could not be funneled away, so the container has been redesigned with a heating system.

Another option is the "junk shot," which would involve trying to plug the leak with assorted junk, including knotted rope, plastic cubes and even golf balls. The process could halt the flow altogether, or at least slow the spill.

The slick has the potential to devastate fragile and environmentally important coastline across a region where many are still recovering from the effects of Hurricane Katrina in 2005.

"I'm not going to rest or be satisfied until the leak is stopped at the source, the oil in the Gulf is contained and cleaned up, and the people of the Gulf are able to go back to their lives and their livelihoods," Obama vowed Friday.

The president said he had ordered "top to bottom" reform of the Minerals Management Service, decrying the "cozy relationship between the oil companies and the federal agency that permits them to drill."

He also promised a review of compliance with environmental regulations after reports that MMS allowed BP and other oil firms to drill in the Gulf of Mexico without the required permits.