WASHINGTON (CNN) -- The influential former chairman of the Senate Armed Services Committee has called on President Bush to start the process of bringing U.S. troops home from Iraq in September.
Republican Sen. John Warner opposed the "surge" policy.
Sen. John Warner, a Virginia Republican, said Thursday that a pullout was needed to spur Iraqi leaders to action.
He has recommended Bush announce the beginning of a U.S. withdrawal in mid-September, after a report is released from the top U.S. officials in Iraq, and that those troops should be back in the United States by Christmas.
"In my humble judgment, that would get everyone's attention -- the attention that is not being paid at this time," Warner said.
He added: "I really, firmly believe the Iraqi government, under the leadership of Prime Minister [Nuri] al-Maliki, let our troops down." Watch what Warner's call does for fellow Republicans »
In Texas, where Bush is on vacation, National Security Council spokesman Gordon Johndroe said the White House appreciated Warner's advice.
"That will be the time, in September, to hear these reports and then make decisions about the way ahead," Johndroe said.
But he added, "I don't think that the president feels any differently about setting a specific timetable for withdrawal."
Warner opposed Bush's January decision to send nearly 30,000 additional U.S. troops to Iraq. But he has so far also opposed Democratic efforts to force Bush to start bringing U.S. troops home.
The "surge" campaign was aimed at buying time for Iraq's government to reach a political solution to the sectarian and insurgent warfare that has wrecked the country since the U.S. invasion in 2003.
The U.S. intelligence community's latest report on Iraq, released Thursday, found "measurable but uneven improvements" in security in recent months. However, it concluded that Iraq's political leaders "remain unable to govern effectively."
But Johndroe said the report also found that U.S. troops have "really helped to improve the security situation on the ground."
"If they were to leave anytime soon, those security gains could be lost," he said.
Democrats have tried to wind down the war since taking over Congress in January, but Senate Republicans have used filibuster tactics to stymie those efforts.
After Thursday's report, Senate Majority Leader Harry Reid called on Republican senators to join Democrats to force Bush to change course -- and a senior Democratic leadership aide urged Warner to add his vote to those efforts.
"Will he [Warner] vote with us on anything? That is still the open and most important question," the aide said. "A recommendation to the president is different than voting for binding legislative language compelling the president to act."
Warner is one of the most respected voices in the Senate on military and national security issues.
Besides being a former Armed Services chairman, he was a secretary of the Navy in the 1970s. Warner served in the Navy in World War II and in the Marine Corps during the Korean War. He has been in the Senate for five consecutive terms.
He and the current Armed Services chairman, Michigan Democrat Carl Levin, recently returned from a visit to Baghdad with harsh words for the al-Maliki government.
Levin said Monday that Iraq's parliament should throw al-Maliki out of office and replace his government.
Warner said he would not join that call. "But in no way do I criticize it," he added.
Warner met at the White House earlier Thursday with Lt. Gen. Douglas Lute, the White House official responsible for coordinating Iraq issues.
Warner said the president and other leading Bush administration officials have repeatedly said the American commitment to Iraq was not open-ended.
"The time has come to put some meaningful teeth into those comments -- to back them up with some clear, decisive action," the senator said. E-mail to a friend