The unidentified spokesman told the Platts energy news service in an article published Friday it's not possible to build a oil pipeline in the time expected by Kurdish officials.
Ashti Hawrami, natural resources minister for the semiautonomous Kurdistan Regional Government, said last week it would take less than two years to build a pipeline to carry 1 million barrels of oil per day from Kurdish fields through Turkey.
Pipelines in northern Iraq have been the target of frequent terrorist attacks.
Officials in the semiautonomous Kurdish north of Iraq blamed al-Qaida for a string of bombings in Erbil, the Kurdish capital, that left six people dead and more than 40 others injured in late September.
The Kurdish government has been locked in a heated debate over oil revenue with the central government in Baghdad.