WASHINGTON (CNN) -- Two leading Republican senators say they will challenge President Bush to offer a plan to start reducing U.S. forces in Iraq by the end of the year.
Sen. John Warner, left, and Sen. Richard Lugar: There's no excuse for not planning.
Sens. John Warner of Virginia and Richard Lugar of Indiana are proposing an amendment to the Defense Authorization Bill that would also declare the Senate's 2002 authorization for the use of force in Iraq "obsolete" and in need of revision, Lugar says in a prepared statement to be delivered Monday on the floor of the Senate.
"Our amendment mandates that the administration immediately initiate planning for post-September contingencies, including a drawdown or redeployment of forces," Lugar's statement says. "It requires those plans to be presented to Congress by October 16 of this year, and it states that the plans should be designed to be executable beginning not later than December 31."
Lugar's statement says the buildup of troops in Iraq "must not be an excuse for failing to prepare for the next phase of our involvement in Iraq, whether that is withdrawal, redeployment, or some other option. We saw in 2003 after the initial invasion of Iraq, the disastrous results of failing to plan adequately for contingencies."
Gen. David Petraeus, the top U.S. commander in Iraq, will report to Congress on the state of the war in September.
White House Deputy Press Secretary Tony Fratto said the administration will review the statement carefully. "As President Bush said yesterday, we believe that the new way forward strategy should be given a chance to succeed. We look forward to hearing from Gen. Petraeus and Ambassador [Ryan] Crocker," Fratto said.
Lugar's statement says in order to "ensure an opportunity to debate the implications of Gen. Petraeus' report, our amendment declares that the rationale given for the authorization to use force, which passed in 2002, is obsolete and requires revision.
"Many of the conditions and motivations that existed when we authorized force almost five years ago no longer exist or are irrelevant to our current situation. Therefore, the amendment states that Congress expects the president to send Congress a new rationale for the authorization at the time of the Petraeus report."
The amendment does not include any mechanism to force the president to comply or punish him if he does not.
Lugar adds, "We want to avoid a drift in Iraq policy that continually references the next report or milestone, even as the fundamental conditions of our intervention in Iraq remain extremely problematic and hazardous."
Because the amendment does not force the president to implement a withdrawal, it may be difficult for the two Republican senators to gain Democratic support, which would be essential to pass the amendment.
A spokesman for Senate Majority Leader Harry Reid, D-Nevada, said Reid appreciated the senators' moves, but said Lugar and Warner put too much faith in the president.
"They clearly recognize there is no purely military solution in Iraq and that the war, on its current course, is making this nation less secure," said Jim Manley, Reid's spokesman. "Unfortunately, Sen. Reid is not as confident in the president's willingness to change course voluntarily in the fifth year of the war."
Reid is backing a Democratic amendment that would require the president withdraw troops from Iraq by April 1, 2008.
The Lugar-Warner amendment will also call for "an urgent diplomatic effort in the region to repair alliances, recruit more international participation in Iraq, deal with refugee flows, prevent aggression, generate basing options, and otherwise prepare for future developments," the statement says.
"This must proceed, now. If we have not made substantial diplomatic progress by the time a follow-on policy is implemented, our options will be severely constrained and we will be guessing at a viable course in a rapidly evolving environment."
The Warner-Lugar amendment acknowledges a report on U.S.-set benchmarks for Iraq that Bush released Thursday. The report shows "satisfactory progress" in eight areas, while highlighting that there's "more work to do" in other areas, Bush said.
Iraqis "have provided the three brigades they promised for operations in and around Baghdad," said the president. However, Iraqis have "not done enough to prepare for local elections or pass a law to share in oil revenues."
Bush also announced Thursday that he's dispatching Defense Secretary Robert Gates and Secretary of State Condoleezza Rice to the Middle East next month to use "the tools of diplomacy to strengthen regional and international support for Iraq's democratic government."
The pair will meet with allies and reiterate the U.S. commitment to the International Compact with Iraq, which was put together in Sharm el-Sheikh, Egypt, in May, Bush said.
On Thursday afternoon, the Democratic-controlled House of Representatives voted 223-201 to require most U.S. troops to leave Iraq by April 1, 2008.
Bush vowed again Thursday to veto any legislation that would establish a timetable for troop withdrawal from Iraq. E-mail to a friend