Sen. Chuck Hagel, an outspoken war critic, called Bush's Iraq policy the most dangerous foreign policy blunder.

Outspoken war critic Senator Chuck Hagel will announce his "future plans" to become a Republican presidential contender on Monday.

In January, Hagel, 60, a decorated infantry sergeant during the Vietnam War, told CNN that he would make a decision about a presidential run "soon."

Hagel, an increasingly vocal critic of the Bush administration's handling of the war, called President Bush's plan this year to increase U.S. troops in Iraq "the most dangerous foreign policy blunder in this country since Vietnam."

Hagel also joined six other Republicans in February to back a nonbinding resolution opposing the troop increase.

"I believed what the administration said, that war would be a last resort," Hagel told Esquire magazine in an interview. "And the second thing is, at a critical time like this, the president needs a strong hand, and to some extent, you've got to trust him, until he lies or screws up or something."

Hagel also told Esquire that Bush appears to believe he's no longer accountable. "You can impeach him, and before this is over, you might see calls for his impeachment. I don't know. It depends how this goes."

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