Iraqi forces head for Baghdad but understaffed-US

WASHINGTON, Feb 3 (Reuters) Iraqi forces are arriving in Baghdad for a new effort to get a grip on the violence plaguing their capital but probably not yet in sufficient strength, US Defense Secretary Robert Gates has said.

Gates also took issue with estimates for the cost of sending extra US combat forces as part of that effort and for the amount of support troops needed to sustain them.

Under the plans to try to clamp down on the sectarian killing and other deadly attacks in Baghdad, both Iraqi and US forces are providing extra troops for the city.

Gen. George Casey, the outgoing commander of US forces in Iraq, said on Thursday Iraqi units were deploying on schedule -- in contrast to previous operations to secure the city -- but only had between 55 and 65 percent of their manpower.

''Fifty-five percent probably isn't good enough,'' Gates told a news conference at the Pentagon.

But he noted many Iraqi troops had to go back to their home regions to deliver their pay to their families and he did not know if the units would be better staffed by the time they faced combat.

Marine Gen. Peter Pace, chairman of the US military's joint chiefs of staff, said the Iraqi units would need to increase their strength to be combat-ready.

''They do need to continue to flesh out those units, get all those who may be home taking their money to their families and get them in,'' he said, speaking at the same news conference.

President George W Bush said last month he would send some 21,500 extra US troops to Iraq, with the bulk of them heading for Baghdad, in an effort to get a grip on the violence.

The nonpartisan Congressional Budget Office estimated that the troop increase could cost about 13 billion dollars for a four-month mission and said the combat forces may have to be augmented by up to 28,000 support troops.

''The CBO study, I think, dramatically overstates both the cost and the personnel,'' Gates said.

He suggested the number of support troops could be between 2,800 and 4,200.

''We think that number -- it's not settled for sure right now -- but that number looks, right now, like it will be about 10 percent to 15 percent of the number that CBO cited,'' he said.

Gates did not give a cost estimate for the troop increase, which he has said he hopes will last only a matter of months.

But spokesman Bryan Whitman said the Pentagon stood by its previous estimate of 5.6 billion dollars until the end of the US fiscal year on September. 30.

REUTERS MQA RK1035