The 19-year-old attacking midfielder was allowed to leave the Catalan giants during the summer and has been training at Eastlands for some time, despite interest from Arsenal and Tottenham.
And today he told the club's official website that he was 'excited' by the deal.
City slicker: Gai Assulin has completed his move to Eastlands
He said: 'I had heard a lot about City, and as soon as I saw theclub I wanted to stay. I'm at a great club and I hope to be here a longtime. I have to take my opportunity and learn every day in training.'
In 2008 Assulin became the youngest ever player to be capped byIsrael aged just 16, and made his competitive debut for Barcelona in2009, alongside City's other summer signing from the Camp Nou, YayaToure.
He added: 'I speak with Yaya every day - and I hope to be playing alongside him. I hope to show I can play at this level.'
Assulin has signed a two-and-a-half year deal.
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