Borini earned his move to Liverpool after a superb spell with the Giallorossi.
"It was a very quick negotiation process, partly as I already knew manager Brendan Rodgers and his respect for me," Borini told Vocegiallorossa.
The transfer reunites Borini with Rodgers, who was also his manager at Swansea City from March to May 2011.
"My experience at Roma was certainly a positive one. I think I did well this year, even if I had a few injuries. I believe that I made myself known as a player and got on with the fans.
"I got on best with Miralem Pjanic, Maarten Stekelenburg and Simon Kjaer. I would speak to them in English and therefore help them settle in better. In my view, Pjanic can make the difference this season. He is a formidable player.
"I will bring with me the heat and the passion for what the fans love more than anything else: Roma and the Giallorossi jersey."