President Barack Obama on Thursday will outline his strategy for closing the U.S. prison at Guantanamo Bay, hoping to defuse a revolt by lawmakers over the fate of an internationally reviled symbol of Bush-era detainee policy.

In a much-anticipated speech, Obama will defend his still-emerging plan to shutter the detention camp at a U.S. Naval base in Cuba as he tries to ease concerns that some terrorism suspects held there could be set free in the United States.

He had vowed on his second day in office to close the prison within a year as part of his effort to repair America's tarnished image abroad.

At the same time Obama is speaking, former Vice President Dick Cheney, an architect of Bush's detainee policy and a harsh critic of Obama's approach, will be at a Washington think tank giving a speech partly entitled "Keeping America Safe."

But four months into his presidency, Obama suffered a stinging setback on Wednesday when the Senate, controlled by fellow Democrats, blocked the $80 million he had sought for the shutdown until he decides what to do with the facility's 240 inmates.

Democratic lawmakers, worried that some of the prisoners could be jailed or even released in the United States, rebelled against Obama after opposition Republicans threatened to brand them as soft on terrorism.

Despite his high public approval rating, Obama faces a major test of his leadership as he tries to quell a controversy that threatens to divert his attention from his declared top priority of rescuing the ailing U.S. economy.

While most Democrats agree Guantanamo should be closed, they are demanding a detailed plan before releasing funds to launch the process.

If the funds are not released soon, it could be difficult for Obama to meet his January 2010 deadline for decommissioning the prison, which was authorized by President George W. Bush after the Sept. 11, 2001 attacks on the United States and has long been condemned by international human rights groups.

LAYING OUT 'FRAMEWORK'

White House spokesman Robert Gibbs said Obama would lay out a "framework" for the decisions ahead on Guantanamo when he speaks at 10:10 a.m. EDT (1410 GMT) at the National Archives.

Signaling the likelihood Obama would be short on specifics, Gibbs said many details were still to be worked out and the president had not yet decided whether any of the detainees would be sent to prisons inside the United States.

European allies have been reluctant to accept more than a handful of the prisoners.

Gibbs insisted, however, that Obama would not make any decision that "imperils the safety of the American people" and that the president was determined to stick to his self-imposed timetable for turning the page on Guantanamo.

"Members of both parties agree that Guantanamo Bay has become an image for recruitment for terrorists around the world," Gibbs told reporters on Wednesday. "And the president signed an order early in his administration to close it, and he intends to keep that promise."

At the time, Obama also won praise internationally for banning harsh interrogation methods like "waterboarding," or simulated drowning, which human rights group call torture, and for ordering an end to secret CIA jails overseas.

But he has recently faced criticism on the left and the right for new national security decisions, including blocking the release of photos of alleged detainee abuse and reviving military commissions created by the Bush administration to prosecute terrorism suspects held at Guantanamo.

Seeking to wrest back control of the debate, Obama planned to address those issues as well in what White House aides billed as a wide-ranging speech.