Gulf of Mexico oil spill sparks new US drilling ban
White House adviser tells ABC all new drilling is on hold
The US administration has banned oil drilling in new areas of the US coast while the cause of the oil spill off Louisiana is investigated.
White House adviser David Axelrod told ABC TV it wanted to know exactly what led to last week's explosion on the BP-operated rig in the Gulf of Mexico.
As many as 5,000 barrels of oil a day are thought to be spilling into the water, threatening US coastal areas.
Florida Governor Charlie Crist declared a state of emergency on Friday.
The order, which covers Escambia, Santa Rosa, Okaloosa, Walton, Bay and Gulf counties, says the oil slick "is generally moving in a northerly direction and threatens Florida's coast".
Paul Adams, BBC News, Washington
Even as frantic efforts continue to minimise the consequences of last week's oil rig explosion, the political fallout is becoming clear.
A month ago, the administration said it was willing to lift a decades-old ban on offshore drilling.
It was seen as a gesture to Republican opponents of President Obama's wider energy policy and his efforts to tackle climate change.
But environmentalists were aghast. Now their worst fears are being realised and so the president's senior adviser has said on TV that there will be no new drilling until there has been what he calls "an adequate review" of what's happened in the Gulf of Mexico.
Whether his comments herald a complete rethink on offshore drilling, it is still too early to say.
Louisiana Governor Bobby Jindal has already declared a state of emergency. The slick from the wreck of the rig has begun to reach the Louisiana shore and on Friday the state's National Guard was mobilised.
Heavy seas on Friday were pushing the slick towards the coast and over the booms meant to contain it.
The US National Weather Service said strong winds, high tides and waves could push the oil into inlets, ponds and lakes in south-east Louisiana over the weekend.
Rescuers poised to treat affected wildlife had their first patient on Friday - a young gannett found offshore covered in thick, black oil.
It was taken to a treatment centre at Fort Jackson, south-east of New Orleans.
Mr Axelrod announced the ban on drilling in new areas on ABC's Good Morning America programme.
He also defended the administration's response to the 20 April explosion that destroyed the BP-operated Deepwater Horizon rig saying: "We had the coast guard in almost immediately."
Last month President Barack Obama eased a moratorium on new offshore drilling.
In a statement outside the White House on Friday, President Obama said he believed oil exploration was an important part of the US economy but it had to be done responsibly.
"BP is ultimately responsible... for paying the costs of response and clean-up operations but we are fully prepared to meet our responsibilities in all affected communities," he said.
He said five staging areas had been set up to protect sensitive shorelines and about 1,900 emergency workers and more than 300 ships and aircraft were on the scene.
We're putting everything forth in plans for a worst-case scenario
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.