The new pipeline will link with the Trans Anatolian Pipeline near the Turkish-Greek border at Kipoi, cross Greece and Albania and the Adriatic Sea, before coming ashore in southern Italy.
The $1.8bn project will initially transport 10 billion cubic meters (bcm) of gas annually, and can be expanded to transport up to 20bcm of gas.
TAP will transport natural gas from the Shah Deniz II field in Azerbaijan to European countries, including Bulgaria, Albania, Bosnia and Herzegovina, Montenegro, Croatia.
First gas sales to Georgia and Turkey are planned for late 2018, while initial deliveries to Europe are expected in 2019.
TAP said that the pipeline in Italy will facilitate transport of Caspian natural gas to European markets, including Germany, France, the UK, Switzerland and Austria.
Earlier this year, TAP invited expressions of interest for the construction of a 105km offshore pipeline section under the Adriatic Sea.
BP, SOCAR and Statoil each own a 20% stake in TAP, while Fluxys, Enagás and Axpo have 19%, 16% and 5% interests, respectively.
