BP begins pressure test to stop oil spill

BP Plc said it began a critical pressure test on its ruptured Gulf of Mexico oil well on Thursday after a delay to fix a leaking hose.

BP is testing its latest cap to the oil well that could staunch all or most of the gushing flow of crude that has been polluting the ocean and coastline for nearly three months in the worst offshore oil spill in US history.

As the company pushed ahead on the spill control effort, US energy company Apache Corp was moving forward on a possible $10 billion deal for some BP properties, including major assets in Alaska, CNBC reported.

Reports that Apache was seeking $6 billion to $7 billion for the purchase helped extend a rally in BP's US shares, bringing them up 2.8 percent in midday trade.

The top US oil spill official backed away from earlier assurances that the new cap would be used to completely seal the well until relief wells eventually kill it with heavy mud and cement.

Retired Coast Guard Admiral Thad Allen said the cap could possibly shut the well, but might also be used only to block the flow during emergency situations like a hurricane, when BP's surface containment effort would be suspended.

"The intention of the capping stack was never to close in the well per se," Allen told reporters in New Orleans. "The best reason to be able to shut in the well right now ... is it allows us to abandon the site if there is a hurricane."

"We can certainly consider shutting in the well -- that is a possibility and of course we would like to do that."

Thursday's test will show whether the cap can shut off flow if oil-capture vessels at the surface must disconnect.

A leak in a line connected to one of the valves in the capping device was the latest setback for the British company, which has seen its share value plummet and reputation battered since the April 20 rig explosion that killed 11 workers and led to the spill of millions of gallons of oil.