The 23-year-old spent last season on loan at the Stadium of Light from Liverpool, scoring 10 goals.
"We've agreed terms with Liverpool and we are waiting for the documents to be signed and then we'll move on from there," Poyet told Sky Sports News. "Like any other deal you do, first you need to sort out the clubs and then you start working with the player.
"I'm hoping we can have him because he knows how much it would mean for us to have a player like Fabio."
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