Two BP rig supervisors charged with manslaughter over the death of 11 workers on the Deepwater Horizon will not go on trial until 2014.
US District Judge Stanwood Duval put off the trial of Robert Kaluza and Donald Vidrine until January 13, 2014.
Prosecutors said they expected to provide more than a million pages of information to the defence and defence lawyers said they needed more time to prepare for the trial, which had been scheduled for February 5.
Separately, underwater inspections at the site of the Deepwater Horizon disaster have failed to identify the source of a persistent sheen on the surface of the Gulf of Mexico.
Both the US Coast Guard and BP said the recent inspections confirmed that the company's Macondo well, which blew out in April 2010 and spawned America's worst offshore oil spill, remained secure and was not leaking oil.
Relief wells that were drilled in 2010 to stop the gusher also were found to be secure during the four-day survey, BP said. But investigators collected samples of a white, cloudy substance that appeared to be coming from several areas on the overturned rig on the sea floor. Lab tests were planned on the samples of the substance, which is not believed to be oil.
"No apparent source of the surface sheen has been discovered by this effort," coastguard captain Duke Walker said. "Next steps are being considered as we await the lab results of the surface and subsurface samples and more detailed analysis of the video shot during the mission."
Robot submarines were used to inspect the rig, portions of the riser that once connected the rig to the sea floor and an 86-ton steel container that was lowered over a leaking drill pipe in the spill's aftermath. The survey was focused on seeing if any oil from the 2010 spill is still trapped in the wreckage.
BP said the latest survey, which ended on Saturday, marked the fourth time since the well was sealed permanently in September 2010 that inspections had confirmed it was not leaking.