World Finn class champion Ed Wright is joining what is a second Italian America's Cup challenger but wearing Spanish colours announced in Valencia, which hosted the last two events.
Green Comm Racing, which has been organising itself since 2009, said it would have a budget of €40m, of which it already had over 50 per cent.
It will be buying a standard design package for the eventual 72-foot wing-powered catamaran from America's Cup Race Management and will be using aerodynamic research work already being done by the University of Pisa.
Sporting director Luca Devoti, a Finn class silver medallist at the Sydney Games in 2000 and chief executive of the +39 America's Cup challenge in 2007, said: "It will be really tough to catch up the big teams like the American defender, Oracle, the challenger of record, Sweden's Artemis, and Team New Zealand.
"It will be immensely difficult, but we think we can do it." He hopes to take delivery of the 45-foot wing-powered catamaran that will be used in the first series of races, starting in Cascais, Portugal, in August and followed by Plymouth in September and San Diego in November.
The Green Comm team has challenged through the Real Club Náutico de Valencia and will be based their, train there and build its boat there.
"But this is not just about Valencia, though we feel at home here, not just about Spain but about Europe," said the team's founder Francesco De Leo, who added: "And we hope to build a bridge to California and Silicon Valley."
In welcoming a seventh country to the challenger list, Richard Worth, chief executive of America's Cup Event Authority, also revealed that a $50m. budget had been set aside for television coverage over the next two years.
Ed Wright, who has been in a three-way battle to represent Britain in the Finn class in Weymouth next year – Ben Ainslie is favourite to try for a fourth consecutive gold medal – had flown in from Kiel, where he had won the Finn class. Megan Pascoe won the 2.4M paralympic class.