BRUSSELS—Afghan security forces continue to have leadership problems, weaknesses that are the focus of the continuing NATO training mission, the alliance spokesman in Afghanistan said Thursday.

The North Atlantic Treaty Organization command needs to have the ability to regularly advise Afghan corps, the units that oversee broad swaths of the country, as well as occasionally push training and advice down to Afghan kandaks, units of 600 soldiers, U.S. Army Brig. Gen. Charles Cleveland said Thursday.

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