Former US Defence Secretary Donald Rumsfeld proposed major changes to the Bush administration's strategy in Iraq just two days before he resigned.
Mr Rumsfeld had long advocated staying the course in Iraq
He made the call in a classified memo to the White House, which has been obtained by the New York Times.
Mr Rumsfeld's memo says US strategy in Iraq "is not working well enough" and calls for "a major adjustment".
President Bush faces growing pressure to decide a new Iraq course with an advisory group due to report this week.
"In my view it is time for a major adjustment," Mr Rumsfeld wrote in the memo dated 6 November.
"Clearly, what US forces are currently doing in Iraq is not working well enough or fast enough."
US national security adviser Stephen Hadley told ABC TV that President George W Bush agreed with that assessment, describing the memo as a helpful "laundry list of ideas".
Apart from President Bush, the combative Mr Rumsfeld was identified more than anyone else with the US administration's strategy of "staying the course" in Iraq.
So it seems extraordinary that behind the scenes he was calling for major changes, the BBC's James Westhead in Washington says.
However, in recent months he had begun to acknowledge publicly that US tactics were not working and needed to be more flexible, our correspondent notes.
The document, first published by the New York Times and subsequently confirmed by the Pentagon, contains no reference to Mr Rumsfeld's imminent resignation.
Mr Rumsfeld was replaced following Republican losses to the Democrats in the US mid-term elections.
His proposals in the memo include troop redeployments and base closures, in apparent contradiction with his public assertions that it is commanders in the field who determine troop levels.
The memo also suggests "beginning with modest withdrawals of US and coalition forces... so Iraqis know they have to pull up their socks, step up and take responsibility for their country".
The plan would boost training for Iraqi forces, officials said
The US should "stop rewarding bad behaviour", the memo says. Reconstruction efforts should be in those parts of Iraq that are behaving and no more reconstruction assistance should be given in areas where there is violence.
Mr Rumsfeld also urges President Bush to copy the tactics of Iraq's deposed leader: "Provide money to key political leaders (as Saddam Hussein did), to get them to help us get through this difficult period."
Among other options described as "Above the Line" are:
- Significantly increase the number of US trainers and transfer more equipment to Iraqi security forces
- Reduce quickly the number of US bases, currently 55, to five by July 2007
- Position substantial US forces near the Iranian and Syrian borders to reduce infiltration and Iran's influence
- Withdraw US forces from vulnerable positions, such as patrols, and use them as a quick reaction force to help Iraqi security forces when needed
Any new approach should be announced as being on a "trial basis", giving the administration the ability to change if necessary and therefore not "lose", the memo says.
Mr Rumsfeld also outlined a number of "Below the Line" or less attractive options, including continuing on the current path, moving large numbers of US forces into Baghdad and increasing US forces substantially.
Other proposals include setting a firm withdrawal date and pushing an "aggressive" federalism plan to move towards three separate states - Sunni, Shia and Kurd.
News of Mr Rumsfeld's proposals comes as the Iraq Study Group, which brings together senior politicians and diplomats, is preparing to present its findings to Mr Bush.
Their recommendations are widely expected to include a gradual phased withdrawal of US troops over the next 18 months.
Mr Bush has indicated he will look closely at but not necessarily follow the group's suggestions.
"I want to hear all advice before I make any decision about adjustments to our strategy in Iraq," Mr Bush said in his radio address on Saturday.