President George W. Bush will tell the United States this week he plans to reduce U.S. troop presence in Iraq by about 30,000 by next summer, basing those and further cuts on continued progress, the Associated Press has learned.

In a prime-time television address on Thursday at 9 p.m. ET, Bush is expected to endorse the recommendations of his top general and top diplomat in Iraq, following their appearance at two days of hearings in Congress.

The White House plans to issue a written status report on the so-called "surge" on Friday, the officials said, speaking on condition of anonymity because Bush's speech is not yet finally drafted.

White House officials were preparing the address even as the U.S. commanding general, David Petraeus, and U.S. ambassador to Iraq Ryan Crocker were presenting arguments to stay the course in Iraq in a second day of testimony on Capitol Hill.

Republicans skeptical over war policy

During a Senate foreign relations committee hearing Tuesday,  Republicans sharply challenged both Petraeus and Crocker in a sign that some within the party retain serious misgivings about the protracted war.

"Are we going to continue to invest blood and treasure at the same rate we're doing now? For what?" asked Senator Chuck Hagel, who supports legislation setting a deadline to bring troops home.

The deep-seated doubt expressed at the hearing reflected just how far Congress had come since the war began over four years ago, as Republican senators raised tough questions that rivalled those asked by Democratic presidential hopefuls on the panel.

The exchanges came just a day after Petraeus recommended keeping the bulk of U.S. forces in Iraq — some 130,000 troops — deployed there through next summer.

While Republicans were once deferential to the thinking of officials running the war, particularly uniformed officers, Hagel and other GOP senators on the panel said they doubted that simply giving war commanders more time would necessarily yield results.

"In my judgment, some type of success in Iraq is possible, but as policymakers, we should acknowledge that we are facing extraordinarily narrow margins for achieving our goals," said Senator Richard Lugar of Indiana, the top Republican on the committee.

Senator Norm Coleman said he appreciates plans to return troop levels to 130,000 — down from the 168,000 currently in Iraq — but that he wants a longer-term vision other than suggestions that Petraeus and Crocker will return to Capitol Hill in mid-March to give another assessment.

"Americans want to see light at the end of the tunnel," Coleman said.

Echoing testimony given to the House on Monday, Petraeus and Crocker acknowledged that Iraq remains largely dysfunctional, but said violence in recent months had decreased since the influx of the added 30,000 troops deployed earlier this year.