But Army General George Casey also told a Senate panel today that the buildup of 21,500 soldiers and Marines as ordered by Bush would give greater flexibility in doing the job.
Casey said he does not believe current U.S. policy has failed in Iraq. He said the struggle is winnable, but it will take patience and will.
The senators are considering Casey's nomination to be U.S. Army chief of staff.
Meanwhile, more than 80 people were reported killed in Iraq today, while security officials said sectarian attacks claimed the lives of nearly 2,000 civilians throughout the country in January.
Two suicide bombers killed 57 people when they struck a packed market in the center of Al-Hillah, south of Baghdad.
In the capital, at least 16 people were killed in separate incidents.
Eight more people, including a U.S. soldier, were killed across the country.
A mass grave was discovered in the deserted southern governorate of Al-Muthanna that holds up to 250 bodies, believed to be those of Kurds.
In its annual survey of global press freedom, meanwhile, Reporters Without Borders said the deaths of 65 media workers in Iraq last year account for more than half of 110 such deaths worldwide.
(compiled from agency reports)