The US government's oil spill chief has tried to tamp down fears that BP's capped well is buckling under the pressure, saying that seepage detected along the sea floor less than two miles away is coming from an older well no longer in production.
Retired Coast Guard Admiral Thad Allen also said at least five leaks have been discovered around the well machinery, but he dismissed them as "very small drips" - "not unlike an oil leak you might have in your car".
Over the past few days, since a 75-ton cap was placed over the well to keep the oil bottled up inside, BP and government engineers have been watching closely to see whether the well would hold tight or show signs of rupturing under the pressure. A rupture could cause a bigger and harder-to-control disaster.
Admiral Allen has granted BP repeated 24-hour extensions to keep the cap in place, as long as the company monitors the well scrupulously.
Meanwhile, the end game in the three-month crisis appeared to be drawing closer, with BP vice president Kent Wells saying the drilling of the relief well - necessary to permanently plug up the well - is on track. He said crews hope to drill sideways into the blown-out well and intercept it at the end of July.
At that point, they will begin the kill procedure - pumping mud and cement into the hole deep underground to seal it up once and for all. BP said that stage could take anywhere from five days to a couple of weeks.
"Everything's looking good," Mr Wells said. "The relief well is exactly where we want it. It's pointed in the right direction, and so we're feeling good about that."
BP wants to leave the cap on in the meantime. At one point, Allen wanted instead to relieve the pressure by opening up the cap and siphoning oil up to ships on the surface, but he has relented in the past few days. Opening up the cap would have required allowing millions of gallons (liters) to gush into the sea again for a few days while the plumbing was hooked up.
The BP-leased Deepwater Horizon rig exploded April 20, killing 11 workers and touching off one of America's worst environmental crises. The well has spewed somewhere between 94 million and 184 million gallons into the Gulf. BP said the cost of dealing with the spill has now reached nearly $4 billion.
BP said it is selling some oil fields and other major holdings in the US, Canada and Egypt to Apache Corp for $7 billion to help cover the costs of the oil spill. Some or all of the proceeds will go toward a $20 billion victims compensation fund that BP agreed to last month under pressure from the Obama administration.