The massive Gulf of Mexico oil spill was called a potential catastrophe by U. S. government and military officials on Sunday.

Rough seas had forced crews trying to deal with the Gulf of Mexico oil spill into a "holding action," U. S. Coast Guard Adm. Thad Allen said in appearances on CNN's "State of the Union."

Asked specifically if he was happy with BP's response to the oil rig explosion that claimed 11 lives and poses an environmental crisis for parts of the Gulf Coast, Allen sidestepped, saying only that the oil company "is the responsible party and they need to be responsible."

Allen said, "I spent a lot of time last night with the senior executives talking about the things we need to do."

She does not think the government relied too heavily on BP's assessment of the damage situation in the first days after the April 20 explosion, Homeland Security Secretary Janet Napolitano said.

She said, "There was independent modeling being done by NOAA (National Oceanic and Atmospheric Administration) and the Coast Guard, based on what they were seeing coming to the surface of the ocean."

From Day 1, authorities started working on the assumption the worst-case scenario could happen with 100,000 barrels of oil or more leaking per day. Estimates now range from 5,000 to 25,000 barrels leaking daily, U. S. Interior Secretary Ken Salazar said.

Allen said, "The difference between the Exxon Valdez and this event is that we had a vessel and once the oil was spilled, we could measure what was left on the vessel and the volume that was left. This spill at this point, in my view, is indeterminate. That makes it asymmetrical, anomalous, and one of the most complex things we've ever dealt with." (With Inputs from Agencies)