Washington ? The outgoing top U.S. general in Iraq diplomatically aired his differences with the commander in chief Thursday, telling lawmakers that President Bush has ordered thousands more troops into Iraq than needed to tamp down violence in Baghdad.

Gen. George Casey quickly added he understood how his recently confirmed successor, Lt. Gen. David Petraeus, could want the full complement of 21,500 additional troops that Bush has ordered to Iraq. Casey said they could “either reinforce success, maintain momentum or put more forces in a place where the plans are not working.”

The latest National Intelligence Estimate on Iraq, delivered to the White House on Thursday, described an increasingly perilous situation in which the U.S. has little control and further deterioration is possible, The Washington Post reported. A two-page summary of the report was scheduled to be released publicly today.

The 90-page classified report comes to no conclusion over the question of whether civil war has engulfed Iraq, unidentified sources familiar with the document told the Post. It says that al-Qaida activities remain a problem but cites Iraqi-on-Iraqi violence as the primary source of conflict and the most immediate threat to U.S. goals, the Post reported in today’s editions.

While optimistic at times about improvement, the report casts uncertainty on whether Iraqi leaders will be able to fight sectarian interests and extremists, establish effective national institutions and stop corruption, the Post said.

As Casey spoke at a confirmation hearing into his nomination to become Army chief of staff, the full Senate lurched toward a widely anticipated debate on the administration’s policy, the first since midterm elections in which public opposition to the war helped install a new Democratic majority.

One day after critics of Bush’s revised war strategy merged two competing Senate measures, the White House worked to hold down the number of GOP defections while two liberal Democrats attacked the compromise as too weak. An early test vote on the issue is tentatively set for Monday.

Gen. George W. Casey Jr. answers a question Thursday during the Senate Armed Services committee hearing on Capitol Hill on his nomination to become Army chief of staff.

“It is essentially an endorsement of the status quo, an endorsement I simply cannot make in light of the dire circumstances in Iraq and the need for meaningful action now,” said Sen. Christopher Dodd of Connecticut, who is seeking the 2008 Democratic presidential nomination.

Casey endured occasional sharp criticism as he appeared before the Senate Armed Services Committee.

“I do not in any way question your honor, your patriotism or your service to our country. I do question some of the decisions and judgments you have made over the past two and a half years as commander of Multi-National Forces in Iraq,” said Sen. John McCain, R-Ariz. “During that time, things have gotten markedly and progressively worse, and the situation in Iraq can now best be described as dire and deteriorating.”

So far, no senators have announced plans to oppose Casey’s elevation to chief of staff, although McCain, as well as Sens. Lindsey Graham, R-S.C. and Joseph Lieberman, I-Conn., said they were undecided how to vote.

In the peculiar politics surrounding the Iraq war, the three lawmakers are among the strongest critics of the nonbinding legislation. It would criticize the decision to increase troops as a way of stabilizing Baghdad nearly four years after Saddam Hussein was forced from power.

They said they intend to advance an alternative measure setting out the goals that should be met by the Iraqi government, and pledging whatever resources Petraeus requests. “We’ve come to the conclusion that the Petraeus strategy … to buy some time for political reconciliation is our best chance for victory,” Graham said.