WASHINGTON — The Obama administration's point man on BP's Gulf of Mexico oil disaster on Thursday dumped cold water on suggestions that BP might be able to plug the well in time for its July 27 announcement of second quarter earnings.

Speaking by conference call to reporters from Theodore, Ala., Allen said he thinks that a mid-August date is still the most realistic for a relief well to have intercepted the runaway well and killed it by filling it with heavy drilling mud and concrete.

"I've been around these folks for long enough to know that you need to under-promise and over deliver," Allen said.

The idea that BP might be able to intercept the well earlier than August was the topic of a Wall Street Journal story Thursday that said company officials are pushing to have the relief well completed by July 27 "in a bid to show investors it has capped its ballooning liabilities." The article also said that the London-based BP was hopeful to have shown progress on the kill by July 20, when British Prime Minister David Cameron is scheduled to visit the White House.

Allen, however, said that while the first of two relief wells is a week ahead of schedule and only a few hundred feet from its intended target more than three miles below the surface of the Gulf of Mexico, the final steps in the process are complicated ones. Much can go wrong.

The relief well reached a critical stage June 23, when technicians began using specialized electronic tools to try to locate the steel pipes of the runaway Deepwater Horizon well. Since then, they've run at least seven such "ranging" tests to home in on the well and are now drilling, Allen said, in 15-foot segments. After each such segment, technicians conduct another ranging test.

Those tests, however, are inexact guides for the drill — enough so that Allen has said in previous briefings that BP is keeping thousands of barrels of heavy drilling mud on hand in case drillers "nick" the well prematurely.

The progress is excruciatingly slow. BP announced earlier in the week that the relief well reached a measured depth of 17,725 feet from the Gulf surface on Sunday, and Allen on Thursday gave the depth as 17,780 feet _ meaning the well had been extended 55 feet in four days.

Allen said there were still several hundred feet vertically to go _ and seven to 10 days of drilling _ before technicians would be in a position to turn the drill bit horizontally and head directly for the well bore, which at that point may be just 15 feet away.

What happens then is unknown, Allen said, in large part because engineers do not know the condition of the wellbore and whether oil is flowing between the rock of the seabed and the pipe of the well in an area known as the annulus.

If oil is discovered there when the wellbore has been penetrated, Allen said engineers would first have to pump heavy mud and concrete into the annulus in an effort to stop the oil, a process that could take seven to 10 days. Then drillers will have to drill again into the runaway well to penetrate the steel pipe and repeat the mudding process — another seven to 10 days.

Expecting all that to happen between now and July 27, Allen said, is unrealistic.

Of more immediate concern is whether weather conditions will calm enough for Obama administration officials to feel comfortable allowing BP to remove the current containment cap that is sitting loosely atop a sheared-off pipe and replace it with a new one that would be bolted in place and allow the collection of between 60,000 and 80,000 barrels per day.

That process is expected to take seven to 10 days, during which time oil that's been collected through the cap by the Discoverer Enterprise drill ship would be allowed to gush directly into the sea. A sudden storm and high seas could interrupt the work and extend that time.

On Thursday, Allen gave BP's managing director, Bob Dudley, 24 hours to provide a detailed plan for how such a switch would be accomplished, how long it would take and what BP would do if the installation effort should fail.

Allen said that plan would be reviewed by the Federal Scientific Technical Team in Houston on Friday and that no steps in the process should be taken unless Allen had approved each of them in advance.

On Wednesday, BP collected about 24,575 barrels a day through two vessels attached to the runaway well. The Discoverer Enterprise took in 16,655 barrels through the current containment cap and the Q4000 drilling rig burned 7,920 barrels that it drew directly from the well's failed blowout preventer.

Allen said weather conditions have eased enough that work can be completed to attach a third ship, the Helix Producer I, to the well, also through the blowout preventer. That ship has the capacity to collect between 20,000 and 25,000 barrels a day.

Both the Q4000 and the Helix Producer I would continue to collect oil during any change in containment caps.

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