The 38-year-old Swedish striker, who rejoined the club during the January transfer window, missed last Sunday's 1-1 draw against Verona.
But Milan boss Stefano Pioli is hopeful Ibrahimovic, who has scored two goals in five appearances since arriving back in Italy last month, will be fit for the San Siro showdown.
"Zlatan has been completing an individual programme in order to be ready to rejoin the team in training today, and if he passes this final step then he'll be available for tomorrow evening," said Pioli.
"We've done everything we could to help him recover from the flu and his calf problem. He just needs one more full training session with the team."
Milan have not lost since Ibrahimovic, who spent three seasons at Inter earlier in his career, re-signed for the Rossoneri following a two-year spell in America with LA Galaxy.
And Pioli wants his players to match the veteran striker's mentality in Sunday's derby.
Pioli, whose side are ninth in Serie A, seven places and 19 points adrift of their city rivals, added: "Inter did much better than us up until December, but we're doing well now and we're climbing back up the table.
"We prepare for every game with the aim of winning, but there are some games like this which are simply worth more. And in order to win you need to play better than your opponents.
"We'll all need to have Ibra's mentality tomorrow. We'll need to be fired up and excited at the prospect of the game.
"Our team have shown character and courage, we've had more bad times than good and we've reacted in the right way."
Under former Chelsea manager Antonio Conte, Inter have been in fine fettle this term and will be keen to maintain the pressure on table-toppers Juventus.
Inter, who have lost just once in the league this season – a 2-1 defeat against Juve – are three points off the Serie A summit.
"AC Milan are much better than where they're currently at in the table," said Conte.
"They've got a great team and they've added a champion like Ibrahimovic to it. He's brought experience, awareness and confidence.
"I think that it's right that all of the best players are available for the big games, even in terms of entertainment, and I always hope to face the best players in big games like this."