WASHINGTON, Feb. 1 (Xinhua) -- The outgoing top U.S. commander in Iraq George Casey on Thursday defended his job performance, refusing to take the blame for U.S. failures and setbacks in that country.

    "I don't believe that the current policy has failed," he told U.S. senators at the confirmation hearing for this nomination to the post of Army's chief of staff.

    Responding to a question that if he agreed with President George W. Bush's assessment that the previous Iraq strategy may be "a slow failure," Casey said, "I actually don't see it as a slow failure. I actually see it as slow progress."

    The general did not cede an inch when confronting harsh criticism from Arizona Sen. John McCain, a front-runner for the Republican presidential nomination in 2008.

    "I question seriously the judgement that was employed in the execution of your responsibilities in Iraq, " said McCain, who accusing Casey of pursuing a wrong strategy that used too few troops and relied too much on Iraqi troops.

    But Casey said his strategy was successful, noting that now the Iraqis are able to take security responsibilities in three of the 18 Iraqi provinces.

    "The strategy that I articulated here today is my strategy and I believe in it," he said.

    While many lawmakers are questioning Bush's new plan to send more troops to Iraq, Casey threw his weight behind the president's policy.

    Although he said two extra brigades will be enough instead of Bush's plan to send five more brigades, the general said more extra troops will give commanders more flexibility.

    As part of the shakeup of his Iraq team, Bush nominated David Petraeus to succeed Casey as the top commander in Iraq earlier this month and elevated Casey to the post of army chief of staff in Washington.

    There is no risk of these nominations to be rejected by the senate, although McCain heavily criticized Casey's record in Iraq.