Presidents of Turkmenistan and Afghanistan have met to launch the construction of a pipeline that will pump natural gas from Turkmenistan through Afghanistan, Pakistan and India.

Turkmenistan is believed to have the world's fourth-largest gas reserves, but currently exports almost all of it to China.

Turkmen President Gurbanguly Berdymukhamedov on Monday discussed the new pipeline with Afghan President Ashraf Ghani, who hailed it as "extremely important for the entire region," according to Turkmen state media reports. The reports said Tuesday that the two leaders agreed to formally start its construction on Friday.

TAPI, as the proposed 1,735-kilometer pipeline is known, is intended to carry 33 billion cubic meters of gas annually through the Afghan cities of Herat and Kandahar and end up in the India-Pakistan border town of Fazilka.