"[A] wait-and-see approach, Mr Darling is likely to argue, will give a future government more time to restore prudence to the public finances without killing any economic recovery. The Treasury believes that economic uncertainty is so great at the moment that it makes no sense to set a detailed strategy for deficit reduction when any such plans might need to be ripped up in a month’s time."
To my mind, that suggests that Darling won't announce anything like the package of future spending cuts required to drag the public finances back into shape. If so, "uncertainty" will be the excuse. But you suspect the real motivation is No.10's desire to perpetuate the "Tory cuts" dividing line, and to leave the next government clearing up the mess.
P.S. PoliticsHome's panel of 100 insiders has its say on the fiscal tightening question here.