FRANKFURT, Germany - Europe and the United States are preparing to unfreeze billions of dollars in Libyan assets that will be crucial to the country's success after Moammar Gadhafi.

But even after the influx of money, Libya's economic recovery will be neither easy nor rapid. Its valuable oil sector could take a year or more to restart, and the economy will need many reforms after being ruled for decades by the whims of a dictator and his cronies.

As fighting raged Thursday in the capital of Tripoli, rebel leaders eyed the tens of billions of dollars that governments around the world froze during the early days of the uprising.

The money is expected to provide a financial cushion for Libya that would be the envy of other Middle Eastern countries that deposed rulers this year, such as Egypt.

The European Union said Tuesday it was preparing to unfreeze the money once the United Nations gives its approval. President Barack Obama indicated Monday that he was ready to do the same.

Said Hirsh, Mideast economist for the London-based Capital Economics, estimated Libya's frozen assets around $110 billion, about 110 percent of the country's GDP.

"Even if it takes time to recover all of these assets, a small amount will help the interim government in the near term," Hirsh said in a research note. "It is possible that political stability can be quickly restored, and reconstruction efforts can commence."

The White House hoped to release in the coming days $1 billion to $1.5 billion - about half of the Gadhafi regime's liquid assets that have been frozen in the United States.

The U.S. has a total of $37 billion in Libyan assets, most of it in real estate and other property holdings. Germany has some (euro) 7.3 billion, Britain about 12 billion pounds ($20 billion) and the Netherlands (euro) 3 billion. The governments of Austria, Portugal and Spain have not revealed the size of assets seized in their countries.

While they wait for the green light from the U.N., Germany and the Netherlands each agreed to lend the Libyan rebels (euro) 100 million ($144 million) to fund immediate rebuilding and humanitarian needs. The money will then be deducted from the assets they unfreeze.

But while Libya's transition government will be in the enviable position of having billions in cash and no debt, the economy's fundamental health is poor and the outlook uncertain.

Almut Moeller, an expert on European Union foreign policy at the German Council on Foreign Relations, cautioned that Libya will need a functioning government and political stability to achieve an economic revival - and that Europe may find it has limited influence in that regard, as it learned after revolutions in Tunisia and Egypt.

"The country, of course, can only thrive with a flourishing economy, and I think in the case of Libya, it's easier than in Egypt," Moeller said. "For any business to return, a political settlement and a kind of calming down of the situation need to be achieved."

Working in Libya's favor is that many members of the old regime are part of the National Transitional Council, the rebels' government based in the east of the country.

Their presence in the NTC means that economic and political institutions could resume functioning sooner than they did in Iraq after the 2003 U.S.-led invasion that led to the removal of Saddam Hussein's Baath Party elite.

Prospects for re-starting oil production, most of which has been shut down by the fighting, are uncertain. Germany's BASF AG subsidiary Wintershall, which in February shut down operations that produced up to 100,000 barrels of oil per day, was cautious on when it might get back to work.

"At the moment, it is too early to say when, how and under what conditions," spokesman Stefan Leunig told news agency dapd.

In principle, he said, production could resume "within a few weeks" but ramping it back up depends on the state of export infrastructure and a stable security situation.

Italian oil and gas producer Eni, the biggest foreign operator in Libya, predicted it could take a year before oil output is back to normal.

The country, which sits atop Africa's largest proven reserves of crude, has for decades relied on oil revenues to fuel growth.

Because of this, European investment in non-oil areas will prove important. Those investments increased after the last sanctions imposed on Libya for terrorism were lifted in 2006. Petrochemicals, iron and steel production and construction have all grown since then.

The country's political system and the private sector will have to be strong enough to receive foreign investment, and everything suggests they are not.

Institutions common in other countries, and which are vital to economic growth, were largely missing under Gadhafi's so-called Jamahiriya system - best described as rule by the masses.

The Brother Leader, as he was called for lack of an official title, had once moved to disband the government and distribute oil wealth directly to the people because he was unhappy with what he said was endemic corruption.

The private sector, which began to develop after the sanctions were lifted, is, in fact, a case study in crony capitalism, with the success of businessmen depending largely on their links to Gadhafi or others in his regime.

Libya ranked 146th out of 178 countries on the anti-corruption group Transparency International's corruption perception index, tied with Cameroon, Ivory Coast, Haiti, Iran, Nepal, Paraguay and Yemen.

The country's next leaders will face the daunting task of trying to reform the government while also providing for the security that is essential to bringing back the foreign firms that pulled out after the civil war began.

The first step will be "to make sure that the basic infrastructure is working," said John Hamilton, a London-based Libya expert with Cross-border Information and a contributing editor to Africa Energy.

"They need to make sure they don't run out of electricity in the next days and weeks, that they've got the fuel people need to move around, that the hospitals will function."

"If they do that, then they'll start getting the revenue they need to move forward," Hamilton said. "But it's going to be a massive challenge."

El-Tablawy contributed from Cairo. Associated Press writers Geir Moulson in Berlin, Mike Corder in The Hague, David Stringer in London, Alan Clendenning in Madrid, Don Melvin in Brussels and Jim Kuhnhenn in Washington also contributed to this report.