-LRB- CNN -RRB- -- A month after announcing plans to expand offshore drilling , President Obama visited ground zero of the Gulf Coast oil disaster and warned that residents could be facing a `` potentially unprecedented environmental disaster . '' `` The oil that is still leaking from the well could seriously damage the economy and the environment of our Gulf states and it could extend for a long time . It could jeopardize the livelihoods of thousands of Americans who call this place home , '' Obama said Sunday in Venice , Louisiana . The president reiterated that oil company BP is responsible for the leak and will foot the cost of the cleanup . He pledged to `` spare no effort to respond to this crisis for as long as it continues . '' Obama 's remarks were a stark contrast from his late March proposal to open swaths of U.S. coastal waters in the Atlantic Ocean and the Gulf of Mexico to oil and natural gas drilling . Obama said then that the decision did not come lightly , but it was one that he approached with confidence . `` The bottom line is this : Given our energy needs , in order to sustain economic growth and produce jobs , and keep our businesses competitive , we are going to need to harness traditional sources of fuel even as we ramp up production of new sources of renewable , homegrown energy , '' he said as he unveiled his plans . Obama said the federal government would begin the process of leasing some areas off the coasts of Virginia , Alaska and possibly Florida to oil companies for drilling . New offshore drilling in most U.S. waters has been banned since the early 1980s , when mounting public pressure pushed lawmakers into action . A disastrous oil spill off the California coast in 1969 sparked protests that grew into a broader environmental movement , which eventually forced a drilling moratorium . But as the environmental impact of the Gulf Coast spill comes ashore , the appetite for Obama 's offshore drilling plan and the enthusiasm from administration officials appear to have subsided . CNNMoney : Oil spill may threaten offshore drilling plans `` All he has said is that he 's not going to continue the moratorium on drilling , '' White House senior adviser David Axelrod told ABC 's `` Good Morning America '' on Friday . `` No domestic drilling in new areas is going to go forward until there is an adequate review of what 's happened here and of what is being proposed elsewhere . '' Secretary of State Hillary Clinton said Sunday that moving ahead on offshore drilling is `` going to require a balancing act . '' `` That is a national security concern because we have to do better to lessen our dependence on foreign oil . But it has to be done safely . It ca n't be done at the risk of having to spend billions of dollars cleaning up these spills , '' she said on NBC 's `` Meet the Press . '' And Interior Secretary Ken Salazar said Sunday that the Gulf Coast disaster `` sends out the clarion call that we need to diversify our energy resources . '' `` Our intention is to move forward thoughtfully , looking at how we can protect the resources of the United States and making thoughtful decisions , '' he said on CNN 's `` State of the Union , '' noting that deep-water drilling has been done thousands of times without incident . Time.com : Obama promises help , but containing spill is still talk Obama said Friday he still believes that domestic oil production is an important part of the strategy for energy security , but he added , `` I 've always said it must be done responsibly , for the safety of our workers and our environment . '' The president ordered Salazar to conduct a review of the oil spill and report back in 30 days on what precautions , if any , should be required to prevent future accidents . Democratic Sen. Bill Nelson of Florida has asked Obama to shelve his proposal , at least until the cause of the current spill is fully investigated . In a letter to the president , Nelson also said he would file legislation `` that would , for the time being , prohibit the Interior Department from acting on your administration 's plans to expand offshore drilling , including seismic testing and other exploratory operations . '' Florida Gov. Charlie Crist , who in the past has been a proponent of offshore drilling , told NBC 's `` Meet the Press '' that such drilling has `` got to be tabled , for sure . '' White House press secretary Robert Gibbs indicated last week that Obama 's offshore plans are n't set in stone . `` I think our focus right now is , one , the area , the spill , and two , also to ultimately determine the cause of it and see the impact that that ultimately may or may not have , '' he said , noting that Obama 's announcement was the beginning , and not the end , of a longer process . CNNMoney 's Steve Hargreaves contributed to this report .