A shareholder agreement was signed in Ankara for the $11.7bn Trans Anatolian natural gas pipeline project (TANAP) linking Turkey and Greece.
Southern Gas Corridor Closed Joint Stock Company will hold 58% stake in the project. BOTAS and BP own 30% and 12% interests, respectively.
The 1,850km pipeline will transport Caspian natural gas from the Georgian-Turkish border to Turkey's western border with Greece.
The planned capacity of the pipeline is 16 billion cubic metres of natural gas a year in 2020 to be increased to 24 billion cubic metres in 2023 and 31 billion cubic metres in 2026.
It will be linked to the Trans Adriatic Natural Gas Pipeline and deliver natural gas from the South Caucasus Pipeline to Europe via Greece, Albania and Italy as of early 2020.
The pipeline run from the Turkish village of Türkgözü in the Posof district of Ardahan on the Turkish-Georgian border, pass through 20 provinces, 67 districts and 600 villages.
About 80% of the pipeline will be supplied by Turkish manufacturers within the scope of the Main Line Pipes Purchase contracts signed in October 2014.
A group of companies will build the 56-inch part of the line in three phases under the onshore pipeline construction contracts signed in December 2014
The line runs for 1334km from the Turkish-Georgian border to Eskishehir.
The governments of Turkey and Azerbaijan signed a memorandum of understanding in 2011 to develop the TANAP, which will initially take production from the BP Shah Deniz stage two project in Azerbaijan.