A consortium developing a vast new Azeri gas field on Thursday sealed a major deal to supply natural gas to nine European buyers, further securing the Caucasus nation as an alternative energy source to Russia. The Shah Deniz II consortium -- which comprises Britain\'s BP, Azerbaijan\'s SOCAR, Norway\'s Statoil and France\'s Total -- inked deals to supply gas to Europe over a 25-year period. \"The Shah Deniz II gas purchase agreement, the signing of which we witnessed today, is one of the biggest gas deals in the oil and gas industry,\" Gordon Birrell, BP\'s regional director, told journalists in Baku. The buyers involved in the deal are Shell, Bulgaria\'s Burgas, Greece\'s DEPA, AXPO of Switzerland, Spain\'s Gasnatural Fenosa, GDF Suez from France, E.ON of Germany, and Italian Hera Trading and Enel. The consortium has said it aims to extract 16 billion cubic metres (560 billion cubic feet) of gas per year from under the Caspian Sea. Six billion cubic metres of gas will go to Turkey from 2018 and the rest will go to Europe from 2019, after the new TANAP pipeline across Turkey and the TAP pipeline from Turkey to Italy are completed. The TANAP and TAP pipelines are to be the first gas pipelines as part of the EU\'s Southern Corridor policy of having gas supply routes that avoid Russian territory and reduce the bloc\'s dependence on Russian gas.