Europe aims to break Russia's grip on the regional energy sector with Nabucco, though the project is slow to attract formal supply commitments. Nabucco would stretch from Turkey to Austria, crossing Romania, Bulgaria and Hungary, delivering gas by 2015.
Christian Dolezal, a spokesman for the pipeline consortium, told Turkish daily newspaper Hurriyet that shareholders were looking at the infrastructure requirements outside of Turkey.
"Shareholders decided to locate the feeding station on the Iraq-Jordan border instead of Iran," he said."This was a crucial decision. Due to sanctions on Iran it has become impossible to invest in pipelines there."
Dolezal added that around $6 billion will be invested in the Turkish portion of the planned natural gas pipeline.
The European government reached a recent agreement with Baku for Azeri gas to meet some of Nabucco's capacity, which project leaders said was a positive sign.