Spanish energy company Enagas said Tuesday it signed up as a partner for the Trans Adriatic Pipeline for European natural gas needs, project developers said.

The TAP project consortium said Enagas signed on for a 16 percent share, bringing the number of consortium members to six.

BP, the State Oil Co. of the Azerbaijan Republic and Norwegian energy company Statoil are leading the development of a pipeline meant to deliver as much as 700 billion cubic feet of natural gas per year.

"This continues our successful joint-venture model that has brought producers, midstream players and gas buyers together to develop this important project," TAP Managing Director Kjetil Tungland said in a statement.

TAP is slated to transport natural gas from the second phase of the Shah Deniz natural gas field off the coast of Azerbaijan as early as 2019. It's part of the network of pipelines included in the Southern Corridor of gas programs meant to diversify a European energy sector dependent on Russia.

Construction on some phases of TAP begins in early 2015.

The new consortium structure follows the purchase by Enagas and its Belgian energy company Fluxys of the TAP shares owned previously by German energy company E.ON and French supermajor Total. Fluxys increased its stake from 16 to 19 percent.