Goal USA first reported the deal Wednesday, and the expansion MLS club made the official announcement a day later during a news conference in Brooklyn.
“I am really excited about joining New York City FC and helping to play a real part in building something special in one of the sporting capitals of the world,” said Lampard. “The passion of the nation’s fans at the World Cup was second to none and I am looking forward to meeting New Yorkers and tapping into their love of the game. It is a privilege to be able to help make history here in New York City.”
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Lampard, 36, will join former Barcelona and Atletico Madrid star David Villa when New York City FC begins play during the 2015 season.
“It is going to be an exhilarating opportunity for us all to create this fantastic new MLS Club , in a league that is growing quickly in popularity and ability, Lampard said. "Hopefully my experience can help us have an impact in my first season.”
Like Villa, who retired from international soccer with Spain following the World Cup in Brazil, Lampard could join up with Australian side Melbourne City prior to his move to New York in an attempt to maintain his fitness.
Goal understands that Lampard agreed to terms with New York City FC last month and visited Manchester City's Carrington training base on the same weekend as Villa — with the Premier League champion linked with the MLS club and Melbourne City under the City Football Group umbrella.
New York City FC was also hopeful of landing Barcelona midfielder Xavi, although Goal understands the 34-year-old is set to remain at Camp Nou for another season after last-ditch talks with Luis Enrique and president Josep Maria Bartomeu.
Lampard, meanwhile, could follow in Steven Gerrard's footsteps in announcing his retirement from England duty in the coming days.
The midfielder has earned 106 caps for his country but suggested recently that he is considering his international future. Liverpool skipper Gerrard announced his decision Monday to end his Three Lions career.
Along with Lampard and Villa, MLS has added several aging star players during the past year. Former World Player of the Year Kaka joined NYC's fellow 2015 expansion team Orlando City last month, while Toronto FC added veterans Julio Cesar and Jermain Defoe prior to the start of the 2014 season.