Pakistani Minister for Water and Power Naveed Qamar said a pipeline planned from Turkmenistan would go into service as early as 2016.
"The price of gas obtained from this project will be cheaper than the Iran-Pakistan gas pipeline project," he was quoted by Pakistani newspaper the Daily Times as saying. He didn't provide a specific breakdown of costs.
The Turkmenistan-Afghanistan-Pakistan-India natural gas pipeline, he said, was vital for a country coping with an ongoing natural gas shortage.
Washington backs TAPI, which has the support of the Asia Development Bank, over a rival project planned from Iran. TAPI partners have expressed concerns about the various charges tied to the pipeline, however.
Tehran maintains its part of a natural pipeline is completed, though Western sanctions make it difficult for Iran to find new energy customers. Islamabad last week said it could start receiving natural gas through the Iranian pipeline as early as 2014.