(CNN) -- BP reported problems controlling the undersea well at the heart of the largest oil spill in U.S. history and won a delay in testing a critical piece of equipment in March, according to documents released Sunday.

"We are in the midst of a well control situation on MC 252 #001 and have stuck pipe. We are bringing out equipment to begin operations to sever the drillpipe, plugback the well and bypass," Scherie Douglas, a BP regulatory advisor, told the district engineer for the U.S. Interior Department's Minerals Management Service in a March 10 e-mail.

In a follow-up e-mail to the district engineer, Frank Patton, Douglas reported the company wanted to get a plug set in the well before testing the blowout preventer, the massive device used to shut down the well in case of an emergency.

"With the give and take of the well and hole behavior we would feel much more comfortable getting at least one of the two plugs set in order to fully secure the well prior to testing BOPs," she wrote.

When Patton told BP he could not delay a test any longer than it took to bring the well under control, the company won a postponement from David Trocquet, the MMS district manager in New Orleans, Louisiana, the documents show. Trocquet ordered BP to make sure its cement plug was set up and to verify its placement, according to his reply. The messages do not indicate how long the test was postponed.

The exchange was among the documents released Sunday by leaders of the House Energy and Commerce Committee, which is looking into the disaster that killed 11 workers aboard the drilling platform Deepwater Horizon and uncapped a gusher that is now fouling the northern Gulf of Mexico. BP has been unable to activate the well's blowout preventer since the explosion, resulting in up to 19,000 barrels (798,000 gallons) spewing into the Gulf every day.

Appearing on ABC's "This Week," BP Managing Director Bob Dudley said those questions are being addressed by an investigation led by the Coast Guard and the MMS, which oversees offshore oil drilling. BP, rig owner Transocean Ltd. and oilfield services company Halliburton have blamed each other for the disaster

"There were issues of well control, signs out there, and there are strict procedures that are written," Dudley said. Those procedures allow the rig owner "to walk through well control," he said.

"That's what the investigation will take minute by minute," he said. But he said the failure of the well's blowout preventer is a "very troubling" issue that will have repercussions throughout the oil industry.

"It is the piece of equipment that is not expected to fail, and that's going to have implications for everyone around the world," Dudley said.

BP's design of the well has also come under scrutiny in the New Orleans hearings held by MMS and the Coast Guard. BP drilling engineer Mark Hafle testified Friday that he made "several changes to the casing designs" to address problems with the well's cement walls and leaking drilling fluid. But he said the problems had been addressed.

"No one believed there was going to be a safety issue with pumping that cement job," he said.

Halliburton performed the cementing work on the well, and Halliburton worker Christopher Haire told the New Orleans hearings Friday that BP kept changing the dimensions of the well's casing. Meanwhile, BP's investigation "raised concerns about the maintenance history, modification, inspection, and testing" of the blowout preventer, committee chairman Henry Waxman, D-California, reported earlier this month.

The New York Times reported Sunday that BP documents indicated the company had "serious problems and safety concerns" with the rig's well casing and blowout preventer for months. Rep. Ed Markey, a Massachusetts Democrat who leads an Energy and Commerce subcommittee, said he has seen documents that confirm the Times report.

Other witnesses at congressional hearings into the spill have raised concerns as well. Stephen Stone, a laborer on the doomed rig, told the House Judiciary Committee last week that the Transocean crew had to stop drilling four times in the space of 20 days because of the loss of drilling "mud" -- "either because the underground formation was unstable, or because drilling too quickly caused the formation to crack," he said.

And Doug Brown, the rig's chief mechanic, told the Judiciary Committee that cuts to Deepwater Horizon's engineering staff left the crew with a backlog of preventive maintenance to perform. When they complained, he said, "We were always told, 'We will see what we can do.' "