The forecast, which prompted swift criticism from Democrats, means there will still be 8,000 more US troops in Iraq than when President George W. Bush ordered a surge of extra forces in January 2007 to curb violence.

Army Lt. Gen. Carter Ham, director of operations for the US military's Joint Staff, also said it was too soon to predict if troop numbers could go below the pre-surge level of 132,000 any time this year.

There are currently some 158,000 US troops in Iraq.

Extra US troops, co-opting of former Sunni insurgents and a cease-fire ordered by radical Shi'ite cleric Moqtada al-Sadr have all helped reduce violence in Iraq substantially from levels that were close to all-out civil war. But commanders in Iraq have urged a cautious approach to cutting troop numbers, saying security gains remain fragile and violence too high.