Washington: US Defence Secretary Robert Gates says a realistic estimate of next year's war costs is almost impossible to discern, in part because he does not know how many troops will be in Iraq this fall.

The assertion, to be made to Congress today, will no doubt raise the ire of congressional Democrats, who contend the Bush administration is trying to keep these costs from the American public.

"While I would like to be in a position to give you a realistic estimate of what the department will need for (fiscal year) 2009 supplemental funds, I simply cannot at this point," according to Gates prepared remarks for a budget hearing.

"There are too many significant variables in play," he added.

Gates is scheduled to testify before the House and Senate armed services committees. Also testifying will be Adm Michael Mullen, chairman of the Joint Chiefs of Staff. Their written testimony was obtained in advance by The Associated Press.

Mullen will tell the panels that violence in Iraq has "substantially decreased."

"The surge of US forces to Iraq, a well executed counter-insurgency strategy and an Iraqi population increasingly weary of violence, and willing to do something about it, have all combined to improve security conditions throughout much of the country," Mullen states in his testimony.

Source : PTI