President Bush lifted an executive ban on offshore oil drilling first imposed under his father's administration, although new oil exploration on the Outer Continental Shelf will remain off limits until Congress also takes action.
Bush's announcement was a clear effort to put pressure on the Democratic-led Congress in light of rising gasoline prices.
"Now the ball is squarely in Congress's court," Bush said, speaking to reporters in the White House Rose Garden.
"Today, I have taken every step within my power to allow offshore exploration of the OCS. All that remains is for the Democratic leaders in Congress to allow a vote.
"The American people are watching the numbers climb higher and higher at the pump, and they're waiting to see what the Congress will do."
Bush and a growing number of lawmakers have been calling for broader options in dealing with rising energy costs, including $4 per gallon gasoline.
House Speaker Nancy Pelosi and other Democrats dismissed Bush's actions as political gamesmanship designed to enrich the oil companies.
"The Bush plan is a hoax. It will neither reduce gas prices nor increase energy independence. It just gives millions more acres to the same companies that are sitting on nearly 68 million acres of public lands and coastal areas," Pelosi said in a statement.
"If the President wants to bring down prices in the next two weeks, not the next two decades, he should free our oil by releasing a small portion of the more than 700 million barrels of oil we have put in the Strategic Petroleum Reserve.
"It's time to tell the oil industry: 'You already have millions of acres to drill. Use it or lose it.'"
"This proposal is something you'd expect from an oil company CEO, not the president of the United States," said Sen. Barbara Boxer, D-Calif., chairwoman of the Senate Environment Committee. "The president is taking special-interest government to a new level and threatening our thriving coastal economy."
Environmental groups, too, blasted Bush's move.
"President Bush has once again ignored the wise precedent set by his father and taken reckless action that has neither hope of reducing gas prices nor concern for long-term consequences," said Gene Karpinski, president of The League of Conservation Voters.
The Outer Continental Shelf has been a particularly hot debate, with the Bush administration saying new drilling technology would make U.S. shores safe from environmental disaster while helping to drive down prices with greater supplies.
Democrats say energy companies already have plenty of space to look for oil and have stalled on investing in more oil production while reaping record profits.
Bush, trying to ease market tensions and boost supply, called last month for Congress to lift its prohibition before he did so himself.
White House press secretary Dana Perino said Monday that Bush no longer wants to wait. She pinned blame on the leaders of the Democratic Congress, noting that no action has been taken on this issue.
"They haven't even held a single hearing," Perino said. "So we are going to move forward, and hopefully that will spur action by the Congress."
The president, in his final months of office, has responded to record gas-prices with a series of proposals, including more oil exploration. None would have immediate impact on prices at the pump, according to White House officials, who say there is no quick fix. But starting action now would help, they say.
Bush's proposal echoes a call by Republican presidential candidate, Sen. John McCain, to open the Continental Shelf for exploration.
FOX News' Kelly Chernenkoff and The Associated Press contributed to this report.