Clinton, who is seeking re-election in November to the US Senate from New York, said dependence on foreign oil threatened the economy and national security.

"Our present system of energy is weakening our national security, hurting our pocketbooks, violating our common values and threatening our children's futures," Clinton said in a speech at the National Press Club.

With high gas prices and the large profits for oil companies creating a political uproar in Congress, Clinton proposed a temporary two-year fee on some oil company profits to help create a US$50 billion fund for energy research and innovation.

The goal would be the production of 20 percent of US electricity through clean, renewable sources like wind and solar power by 2020. The fund also would create tax incentives for developing more energy efficient vehicles, she said.

The fund also would expand the use of ethanol, a corn-based fuel additive that is popular in the farm state of Iowa, site of the traditional caucus that opens the presidential race.

Republicans criticized Clinton's proposals, noting she had voted against some of President Bush's energy initiatives, including drilling for oil in the Arctic National Wildlife Refuge.

"Senator Clinton's energy policy consists of a unique balancing act involving partisanship, political pandering and yesterday's mistakes," said Tracey Schmitt, Republican National Committee spokeswoman.

Clinton's speech was interrupted by two protesters against the Iraq war who were quickly hustled from the room by security guards. Clinton voted to authorize the war in 2002 and has been criticized for refusing to call for a quick pullout of US troops from Iraq.

Asked whether she regretted her backing of a congressional resolution supporting the war, Clinton said "I regret the way the president used the authority he was given."

She said the installation of an Iraqi government would speed the negotiation of a handover of responsibilities in Iraq, but added "I don't think we're there quite yet."