"We are working on Iran-Pakistan gas pipe line project as it is vital to overcome the energy challenges of the country and it would be completed in three years time," Gilani said during a TV interview, a Press TV correspondent reported.
Tehran and Islamabad formally signed a multi-billion-dollar gas contract in June 2010, based on which Iran's natural gas will be pumped to Pakistan from the South Pars gas field in the southern province of Bushehr.
Iran has already constructed more than 900 kilometers of the pipeline, which is to carry 21.5 million cubic meters of natural gas per day to its eastern neighbor.
The project, which aims to transport gas through a 2,700-kilometre pipeline, was first mooted in 1994 but became stalled after India evaded the talks. Last year, Iran and Pakistan declared they would finalize the agreement bilaterally if India continued to be absent in the meetings.
The US sought to block the deal and use Tehran's nuclear program as a pretext to exert more economic pressure on Iran, which has the world's second-largest gas reserves after Russia.
Islamabad, however, has made it clear to Washington that the pipeline project is essential for Pakistan to meet its energy needs.