WASHINGTON - President Obama will use his speech to the Arab world Thursday to call for billions of dollars in financial assistance to Egypt and Tunisia as part of a comprehensive approach to the "Arab Spring" movement that he hopes will boost democratic reforms and America's reputation in the region.

The aid package, which would unfold over two to three years, would include an estimated $1 billion in debt cancellation, $1 billion in loan guarantees, and several billion more in financing from multilateral institutions such as the World Bank, according to three senior administration officials who briefed reporters on the condition of anonymity under ground rules set by the White House.

Aides declined to detail other parts of the speech, including how Obama will frame the stalled Israeli-Palestinian peace negotiations or whether he will call for Syrian President Bashar al-Assad to step down after his forces have killed hundreds of protesters.

Obama for weeks has resisted calls to act more aggressively against Assad, but on Wednesday he ordered the freezing of any U.S. assets owned by the Syrian leader and six other top officials.

Obama is betting that the time may be ripe for a new American outreach to the region after U.S. forces killed Osama bin Laden, whose terrorist tactics weren't embraced by the Muslim youth backing the "Arab Spring" revolts.

The speech, to be delivered at the State Department, will be translated simultaneously into Arabic, Farsi, and Hebrew.

It comes as Obama prepares to travel to Europe next week, with stops that include a G-8 summit in France, where he and other world leaders will discuss the Arab Spring.

It also comes on the eve of his scheduled meeting Friday in Washington with Israeli Prime Minister Benjamin Netanyahu, and two days after the president was host to Jordan's King Abdullah II.

The aid previewed Wednesday would finance infrastructure and private-sector job creation, aiming to help stabilize countries by giving young adults more opportunity.

By focusing on Tunisia and Egypt, where uprisings swept longtime rulers from power in recent months, Obama wants to "empower positive models of change," one official said, and create a "positive incentive for others in the region who also are working on the reform agenda."

In shaping his approach, the officials said, the president looked to successful transitions to democracy after World War II and the fall of the Berlin Wall and determined that "reinforcing economic growth is an important way of reinforcing a democratic transition."

However, the expectation that Obama won't speak in great detail or impose new demands on Israeli-Palestinian peace negotiations may frustrate the Middle East audience, analysts say.

White House press secretary Jay Carney said the president saw the Arab Spring as "a moment of opportunity" for the United States to recast its strategy in the region, after a decade focused on wars in Iraq and Afghanistan and the search for bin Laden. "That fight against al-Qaeda continues, but there is an opportunity in that region to focus on advancing our values and enhancing our security," Carney said.

With Mideast envoy George Mitchell's resignation from the Obama administration and a new unity pact between Palestinian factions that complicates peace negotiations further, the president's aides have said for days that the Israeli-Palestinian issue won't be the focus of Obama's remarks.

Andrew Exum, a fellow at the Center for a New American Security and a former Army Ranger and civilian adviser to Gen. Stanley McChrystal, said Obama couldn't talk credibly to Arabs about the uprisings without addressing the need for an Israeli-Palestinian deal.

"From the perspective of the people in the Arabic-speaking world, the Palestinian crisis is part and parcel with the other political movements you're seeing, in terms of self-determination, people desiring political freedom," he said. "They're going to ask why it's appropriate to desire political freedom or Tunisia or Syria, but not in the Palestinian territories."

Thursday's speech may serve as the closest thing to an Obama doctrine, since the president and his team have said the U.S. response to each country's uprising must be considered on a case-by-case basis.

Until now, the U.S. response has seemed "piecemeal," said Robert Danin, a senior fellow with the Council on Foreign Relations who was a State Department official under President George W. Bush.

"It's important for the United States to get out in front with its own message," Danin said. "It's going to be very difficult to get this right, and I'm not sure the Arab world is going to focus that much on it. My own experience is that people are focused inward on the region and less focused on what people on the outside will say."