ROME - The United States is trying to free up some of the more than $30 billion it has frozen in Libyan assets so it can better support opponents of Moammar Gadhafi, U.S. Secretary of State Hilary Rodham Clinton told a conference Thursday.

Twenty-two nations and international organizations were meeting in Rome to figure out how to help the Libyan rebels, who say they need up to $3 billion in the coming months for military salaries, food, medicine and other basic supplies.

Clinton said the Obama administration, working with Congress, wants "to tap some portion of those assets owned by Gadhafi and the Libyan government in the United States, so we can make those funds available to help the Libyan people."

The U.S. has already pledged $53 million in humanitarian aid and authorized up to $25 million in non-lethal assistance to the rebels, including medical supplies, boots, tents, rations and protective gear. The first shipment is to arrive in the western, rebel-held city of Benghazi in the coming days.

Clinton declared that ousting Gadhafi was the best way to protect Libya's people.

"We have made it abundantly clear that the best way to protect civilians is for Gadhafi to cease his ruthless, brutal attack on civilians from the west to the east, to withdraw from the cities that he is sieging and attacking and to leave power," Clinton said. "This is the outcome we are seeking."

The Rome conference agreed to establish an internationally monitored fund the rebels can access to provide basic services to the Libyan people, such as food and medicine. Italian Foreign Minister Franco Frattini, co-host of the Contact Group conference, said nations have already pledged $250 million in humanitarian aid.

It will be "an international fund in which nations can make their contributions in a transparent way," British Foreign Secretary William Hague said. Britain has so far provided 13 million pounds ($21.5 million.)

But Britain said it did not plan to offer direct funding to Libya's rebels beyond the aid money and non-lethal equipment -- including satellite phones and body armour -- it has already pledged.

The conference also focused on isolating Gadhafi amid an apparent deadlock in the fighting.

Since the uprising against Gadhafi broke out in mid-February, the two sides have largely been locked in a stalemate. A U.S. and now NATO-led bombing campaign launched in mid-March has kept Gadhafi's forces from advancing to the east, but has failed to give the rebels a clear battlefield advantage.

NATO says its warplanes will keep up the pressure on Gadhafi's regime as long as it takes to end the violence in Libya.

But NATO member nations are increasingly realizing, however, that air strikes and other military action alone won't end Gadhafi's relentless military assault on rebel-held areas, and that funding the opposition as well as working for his ouster could be the key to success.

Clinton said the world must keep isolating the Gadhafi regime, including imposing travel bans on top officials, suspending Libyan embassies and sending envoys to work with the opposition's Transitional National Council.

"Isolating Gadhafi means pulling the plug on his propaganda and incitements to violence," she said.

The conference document said the group "will intensify the pressure on the regime, politically, militarily and economically."

"Time is running out for Gadhafi's regime," it said.

French Foreign Minister Alain Juppe said he expected NATO's military campaign to last "months."

He insisted the Rome meeting showed "the determination of the coalition to maintain all means of pressure to get the departure of Gadhafi, military pressure but also sanctions and other means of pressure, like for example stopping broadcasting."

The meeting also drew the NATO chief, the Arab League, and Mahmoud Jibril, head of the rebels' executive body.

Italy, conference co-host Qatar, and France have given diplomatic recognition to the rebels, who are based in Benghazi. Frattini opened Thursday's closed-door conference with a call for other nations to do so as well.

"This will help strengthen our Benghazi partners and increase the Gadhafi regime's sense of isolation," the minister said.