He said: "Deep down I wanted to test myself in Spain and I'm so happy it's happened. It's sad leaving Liverpool because it's the club I supported as a kid but now I have a fantastic opportunity and I intend to take it.
"Players like David Villa played for Zaragoza and once you walk around the stadium you realise the fantastic history the club has.
"Maybe one day I will wear the red of Liverpool again but for now all I'm thinking about is repaying Zaragoza for the faith they have shown in me. I'm so excited about playing against Real Madrid and Barcelona."