The 38-year-old Swedish marksman heads back to San Siro after finally agreeing to terms following the end of his time at LA Galaxy.
Zlatan Ibrahimovic has returned to AC Milan on a contract until the end of the current Serie A season with the option to extend the deal for a further season.
The 38-year-old former Sweden international had been without a club since the end of his previous contract at MLS club LA Galaxy.
He previously spent two years at Milan, scoring 56 goals in 85 appearances and winning the Serie A title in 2011.
Now, he joins a Milan side fighting for a top-half finish. With 17 games played, Stefano Pioli’s side are in 11th place, with half the points of league leaders and arch-rivals Inter.
He has continued to score prolifically since leaving Italy in 2012, enjoying productive spells with Paris Saint-Germain and Manchester United prior to his move to Los Angeles.
“I’m coming back to a club I hugely respect and to the city of Milan which I love,” Ibrahimovic said. “I’ll fight together with my teammates to change the course of this season. I will do everything to make it happen”.
He will travel to Milan on January 2 to undergo a medical, before joining his new team-mates for training. A press conference is expected to be held once the final details of the move are signed off.
The prolific forward will join Milan’s current top scorers Krzysztof Piatek and left-back Theo Hernandez, both with four goals apiece, in attack.
Having made a name for himself in Italy he is expected to make an instant impact at the Milan based club in a bid to restore the lost glory.
However, it is more than two months since Ibrahimovic’s last competitive match – a 5-3 MLS Cup playoff defeat to Los Angeles FC at the end of October.
He could make his first appearance at home to Sampdoria on January 6, with further fixtures against Cagliari, SPAL, Udinese and Brescia to come in January.
The towering Swede also represented Inter and Juventus earlier in his career. He has twice been top scorer in Serie A, as well as being named Player of the Year three times and Foreign Player of the Year on five occasions.