WASHINGTON (AP) -- The top U.S. commander in Iraq says additional American troops will begin moving into the country in a couple of weeks to train local forces.

Army Lt. Gen. James Terry (AP Photo/Hadi Mizban)

But Army Lt. Gen. James Terry cautions it will take at least three years to build the capabilities of the Iraqi military.

Terry is leading the U.S. campaign to defeat Islamic State militants in Syria and Iraq. He says the challenge is to get Iraqi units trained and back into the fight so they can plan operations to regain contested areas.

Mosul is the largest city in northern Iraq. The Iraqi army wants to launch a counteroffensive to retake Mosul, likely aided by U.S. support and coordination.

More than 1,000 additional U.S. troops are expected to be deployed soon. About 1,700 are there now.

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