The eastern branch includes the Central Asia – Center (CAC) 1, 2, 4 and 5 pipelines, which start from the south-eastern gas fields of Turkmenistan.

Construction began after discovery of Turkmenistan's Dzharkak field in the Amu Darya Basin, and the first section of the pipeline was completed in 1960.

[5] In 2003, the late President of Turkmenistan Saparmurat Niyazov proposed to renovate existing systems and construct a new parallel pipeline to the western branch.

[7][8] On 12 May 2007, Vladimir Putin of Russia, Nursultan Nazarbayev of Kazakhstan and Gurbanguly Berdimuhamedow of Turkmenistan signed a memorandum for renovation and expansion of the western branch of the pipeline.

From there the pipeline system transports gas north-west along Amu Darya to the Kungrad compressor station in Uzbekistan.

From there two lines run northwest to Moscow, and two others proceed across the Volga river to the North Caucasus-Moscow transmission system.

It continues via Uzen in Kazakhstan to the Beyneu compressor station, where it meets the eastern branch of the CAC.