The export contract would be part of a so-called "peace pipeline" project between Iran and Pakistan.
Last May, Iranian media said Iran and Pakistan had signed an agreement on gas exports, but gave no details on its content or make clear whether there were still issues outstanding.
Iran has the world's second-largest gas reserves after Russia. But sanctions by the West, politics and construction delays have slowed its development as an exporter.
Hojjatollah Ghanimifard, a senior official of the National Iranian Oil Company, told the semi-official Fars News Agency the contract would be signed on March 9-10, but did not say where it would take place.
This would pave the ground for undertaking "executive measures" concerning gas exports, Fars said, without giving details.
"It has been agreed that the relevant text on the execution of the defined measures within the peace pipeline project will be signed on March 9-10," Ghanimifard said.
Last year, the head of the National Iranian Gas Export Company (NIGEC), Reza Kasaeizadeh, said Iran would deliver an annual 8 billion cubic meters of natural gas to Pakistan under the agreement.
An Iranian Oil Ministry official had previously said he hoped gas deliveries would start five years after the contract was signed.
India had been part of the $7 billion pipeline project, but stayed away from talks in 2008, saying it wanted to agree transit costs through Pakistan on a bilateral basis first.
Under the original plan, the pipeline would initially carry 60 million cubic metres of gas daily to Pakistan and India, split between each country. Capacity would later rise to 150 million cubic metres. (Reporting by Hashem Kalantari and Hossein Jaseb; writing by Fredrik Dahl; Editing by Kim Coghill)
