Reza Almasi, the managing director at the Iran Natural Gas Transmission Co., said alternative options to deliver gas to Gulf nations are too expensive, Iran's Petroenergy Information Network reports.
"The required investment for pipeline construction under the sea is three times more than the land," he said. "Not to transit its natural gas through Iran, Turkmenistan has to sign a contract with Azerbaijan, Turkey and Armenia."
Almasi noted pipeline transits were among the safest and most reliable ways to transfer natural gas, adding Iran would work to develop its gas pipeline grid to entice future developments.
The Iranian company currently exports natural gas to Turkey and Armenia and imports gas from Turkmenistan.
Iran has lobbied for a role in regional energy security, pushing for participation in the planned European Nabucco gas pipeline.
Iran and Syria, meanwhile, had signed a memorandum of understanding in April for the construction of the Persian Pipeline. Iranian, Syrian and Turkish officials also signed a trilateral package of deals that included the development of upstream activities, drilling and exploration.