The combination of more Sunni fighters in the Iraqi army and a recent backlash against militants will allow U.S.-led troops to leverage their ability to subdue violent areas, according to U.S. military spokesman Maj. Gen. Kevin Bergner.
"Those forces will help coalition forces fight above their weight. They will help offset the reduction in coalition numbers," he told reporters.
The Bush administration plans to withdraw 30,000 American troops from Iraq by July, a reduction which would put the U.S. force level there at about 135,000.
Kurdish officials, meanwhile, have delayed for six months the explosive issue of a referendum to decide if the oil-rich northern city of Kirkuk will become part of their self-rule area or remain under control of the Shiite-dominated central government.
There was no immediate comment from the Iraqi government in Baghdad, but the referendum was widely expected to be delayed by months.
Kirkuk is an especially coveted city for both the Shiite-dominated Iraqi government in Baghdad and the Kurdish one in Irbil, largely because much of Iraq's oil wealth lies below it.
The Iraqi constitution requires that a referendum on the future status of the city be held to determine whether it will remain under Baghdad's control, become part of Kurdistan or gain autonomy from both.
U.S. Embassy spokesman Phil Reeker told reporters there was no doubt that improvements were made in Iraq during the past year, particularly in security.
"It is pretty clear that 2007 comes to an end in Iraq with Iraq as a substantially better place than where we began the year," he said.
Both Reeker and Bergner told a news conference that the sharp reduction in violence seen in Iraq since the influx of U.S. troops in June gives Iraq's leaders the chance to fix problems that are standing in the way of longer-term stability.
An important factor in the planned drawdown of U.S. troops has been the explosion of so-called "awakening councils" - anti-al Qaeda in Iraq groups that once fought against American and Iraqi troops but who have now turned their guns on extremists.
"As with any transition, there is a need to help build confidence, expand the trust between individuals who at one point had been fighting against Iraqi forces or against the coalition and are now willing to serve alongside them," Bergner said.
The mostly Sunni awakening groups - there are about 300, encompassing more than 70,000 fighters - worry the Shiite-dominated government, which fears they could become an uncontrollable force that would ignite renewed sectarian fighting.
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