El Shaarawy was loaned out to Roma with the option of making the deal permanent for $20 million last season.

The Italy international hit the ground running at the Giallorossi, with eight goals in 16 appearances, earning himself a four-year deal at the club. 

"Today is a very important day for me because I have become in effect a Roma player," he told the club's official website.

"I would like to thank the president [James] Pallotta, the sporting director [Walter] Sabatini, the coach [Luciano] Spalletti, my team-mates and the entire AS Roma for the trust they have shown me since day one, and especially the Giallorossi fans who welcomed me with warmth and affection."

AC Milan confirmed the news on it's twitter account.