The Uruguayan forward, winner of the FIFA World Cup Golden Ball in 2010, scored just twice in 20 appearances for the Nerazzurri after joining from Atletico Madrid last summer.
Inter changed their manager twice during a tumultuous Serie A season and ultimately could only finish sixth, missing out on qualification for the Champions League.
The former Manchester United striker has now joined Brazilian club Internacional on a free transfer after rescinding his contract at the San Siro.
He told Sky Sport Italia: "I enjoyed my season at Inter where there were some excellent people.
"But sometimes you play well and sometimes you don't. Nobody had a really good season at Inter last season.
"I now have the opportunity to play football in Brazil and I want to make the most of it."