"There is flow coming up the pipe," he said. "Just now, I don't know the exact rate."
Robots a mile beneath the Gulf positioned the inverted funnel-like lid over the main pipe on the leaking well Thursday night. Live video footage, though, showed that the oil seemed
To put the cap in place, BP had to slice off the pipe with giant shears, which was risky because it could temporarily increase the flow by as much as 20 percent.
Suttles also told CBS that "I'd like to see us capture 90 plus percent of this flow. I think that's possible with this design."
The news came as President Barack Obama called off an overseas trip and prepared for another visit Friday to the spill-stricken U.S. Gulf Coast.
‘Pleased so far’ June 4: BP COO Doug Suttles talks about the company’s progress on the “cut and cap” procedure to stem the flow of oil into the Gulf.
Live video provided by BP showed dramatic scenes of the cap being lifted into place and dark clouds of oil billowing out from between it and the sawed-off pipe, 5,000 feet below the Gulf's surface.
The gushing oil made it very difficult to tell if the cap was fitting well.
In a column published Friday in the Wall Street Journal, BP Chief Executive Tony Hayward wrote that the latest approach "should enable us to contain and collect the majority of the oil and gas flowing from the well."
'Just the beginning'
Earlier, Hayward promised the company would clean up every drop of oil, and "restore the shoreline to its original state."
"We will be here for a very long time. We realize this is just the beginning," he added.
The plan collect oil brought to the surface in ships so it can be safely removed.
At this depth a mile underwater, the near-freezing temperatures can cause a buildup up of such hydrates, which foiled the company's attempt to place a 100-ton, four-story dome over the leak about a month ago.
But this time methanol was to be pumped in to try to stop the ice-like crystals from forming this time.
The next chance to stop the flow won't come until two relief wells meant to plug the reservoir for good are finished in August.
A rubber seal on the inside will attempt to keep oil from escaping, though engineers acknowledge some crude will still come out.
Facing a criminal probe by the U.S.
government amid mounting civil lawsuits, plunging shares and growing questions about his credit-worthiness, BP planned an eagerly awaited conference call at 9 a.m. EDT with financial market analysts.
BP's shares have plunged almost 40 percent since the rig explosion on April 20, erasing nearly $70 billion in value.
The spill has cost the company more than $1 billion to date. Wall Street analysts say the final bill could be 10 to 20 times that amount, when fines, lawsuits and years of cleanup are taken into account.
Gusher of criticism June 4: With the Gulf well still leaking and the government seeming powerless in stopping it, the president is set to make a return trip to Louisiana.
Confronting one of the biggest tests of his presidency as his party girds for tough congressional elections in November, the White House said Obama called off a trip to Australia and Indonesia set for this month to focus more on the oil spill and other matters.
The White House said in a statement early Friday that Obama spoke Thursday night to Australian Prime Minister Kevin Rudd and Indonesian President Susilo Bambang Yudhoyono to inform them of his decision. The trip had been scheduled for June 13-19.
Prior to today's news, crude oil was pouring unchecked into the Gulf of Mexico at up to 19,000 barrels (800,000 gallons) a day since an explosion April 20 that demolished a BP-contracted drilling platform off the coast of Louisiana, killing 11 crewmen and unleashing an environmental disaster of epic proportions.
With television news footage increasingly filled with images of toxic black goo lapping into fragile marshlands and coating sea birds, Obama has come under growing political pressure to take more decisive action on the crisis.
Obama's trip Friday to the Gulf Coast, his third to the region since the rig explosion, will include discussions with "real people," including residents and business owners affected by the calamity, the White House said.
In an interview Thursday with CNN's Larry King, Obama expressed dissatisfaction with the pace of BP's reaction to the spill, saying, "What I haven't seen as much as I'd like is the kind of rapid response."
The White House said the federal government was sending BP a $69 million bill for costs linked to the spill.
Louisiana is the state hardest hit so far by oil, though the spill also has fouled beaches in Mississippi and Alabama. Government fishing restrictions across much of the region have idled many thousands of fisherman, shrimpers and other seafood workers.
Oil drifted six miles from the Florida Panhandle's popular sugar-white beaches, and crews on the mainland were doing everything possible to limit the catastrophe.
Forecasters said the oil would probably wash up by Friday, threatening a delicate network of islands, bays and beaches that are a haven for wildlife and a major tourist destination dubbed the Redneck Riviera.
Officials said the slick sighted offshore consisted in part of "tar mats" about 500 feet by 2,000 feet in size.
Mark Johnecheck, a 68-year-old retired Navy captain from Pensacola, sat on a black folding chair as rough surf crashed ashore at Pensacola Beach and children splashed in the water. Johnecheck has lived in the Pensacola area since the 1960s, but doesn't come to the beach very often.
"The reason I'm here now is because I'm afraid it's going to be gone," he said. "I'm really afraid that the next time I come out here it's not going to look like this."
Anne Wilson, a 62-year-old retired teachers aide who has lived in Pensacola Beach for the last year and a half, felt helpless.
"There's nothing more you can do," said Wilson, who lived in Valdez, Alaska, near the Exxon spill in 1989. "It's up to Mother Nature to take care of things. Humans can only do so much."
The effect on wildlife has grown, too.
The U.S. Fish and Wildlife Service reported 522 dead birds — at least 38 of them oiled — along the Gulf coast states, and more than 80 oiled birds have been rescued. It's not clear exactly how many of the deaths can be attributed to the spill.
The U.S. National Center for Atmospheric Research projected that the oil slick would be driven by wind and currents around the Florida peninsula by early summer and up the East Coast, possibly as far as North Carolina.
he Associated Press, Reuters and msnbc.com staff contributed to this story.