Murtha called the war in Iraq "a flawed policy wrapped in illusion."

WASHINGTON (CNN) -- One of the leading House Democrats on defense issues on Thursday called for a swift U.S. withdrawal from Iraq, drawing strong criticism from Republicans and escalating the debate over President Bush's war policies.

"U.S. and coalition troops have done all they can in Iraq," said Rep. John Murtha, a Pennsylvania Democrat who has been in Congress for 31 years. "It's time for a change in direction."

Murtha warned that other global threats "cannot be ignored."

Murtha, a retired Marine colonel who earned a Bronze Star and two Purple Hearts for his service in Vietnam, said he believes all the forces could be redeployed over six months. (Watch Murtha's take on 'flawed policy wrapped in illusion' at CNN.com)

Understanding that Murtha is considered hawkish on defense issues and is influential with both parties, administration officials said they take solace that moderate Democrats have not raced to join Murtha's call.