A top adviser to President Barack Obama says no new drilling will be authorized until authorities learn what casued the explosion of the rig Deepwater Horizon.
David Axelrod also defended the administration's response to the April 20 accident, saying "we had the Coast Guard in almost immediately."
He deflected comparisons with the government's slow response to Hurricane Katrina in 2005, telling ABC's "Good Morning America" that such speculation "is always the case in Washington whenever something like this happens."
Obama recently lifted a drilling moratorium for many offshore areas, including the Atlantic and Gulf areas. But Axelrod said Friday "no additional drilling has been authorized and none will until we find out what has happened here."
The White House sharply stepped up its response to the slick, which cast a shadow on the plan Obama proposed a month ago to encourage more offshore drilling in hopes of wooing Republicans to support a bill to tackle climate change.
Obama said on Thursday the administration would use every resource at its disposal, including the military, to stop the spill and help alleviate its impact.
The rig, owned by Transocean Ltd, was finishing a well for BP Plc about 40 miles from the mouth of the Mississippi River when it exploded.
The spill fueled the anger of environmentalists who had criticized his administration's plan unveiled on March 31 to expand drilling after a decades-long moratorium on oil exploration in most of areas of the U.S. coast outside the Gulf of Mexico.
"Today's images of burning oil on the waters of the Gulf of Mexico and the tragic loss of life in the explosion of the Deepwater Horizon provide a grim reminder of the risks posed by oil and gas exploration to the environmental and economic well-being of coastal regions, including the Arctic," William Eichbaum, vice president for Arctic and marine policy at the World Wildlife Fund, said in a statement.
Their reaction could add to pressure on many of Obama's fellow Democrats not to support the bill.
Florida Democratic Senator Bill Nelson said he was filing legislation to temporarily ban the administration from expanding drilling, citing the risk of a potential "environmental and economic disaster."
The White House defended the program, promising to work closely with members of Congress and state governors in any process to open up new areas to offshore drilling and do everything possible to minimize risks.
Administration officials said they would push ahead with efforts to get the climate bill passed.
"Obviously this will become, I think, part of the debate; that goes without saying," said Carol Browner, Obama's top energy and climate adviser. "But I don't think it means that we can't get the kind of important energy legislation that we need."
The climate change bill, one of Obama's top priorities and a centerpiece of his energy policy, had already suffered a severe setback in recent days, when a fight over immigration derailed plans to unveil a compromise measure.
(Additional reporting by Jeff Mason; editing by Alistair Bell and Mohammad Zargham)