Ibrahimovic has just finished his first campaign in North American football and has been linked with a possible departure in the offseason, per Football Italia, but it was confirmed the Swede remains under contract for next season.
The 2019 MLS season doesn't begin until March next year, and Milan wouldn't be able to officially complete a move for their former forward until January 1, when Europe's winter transfer window opens.
Defenders Michael Ciani and Ashley Cole were among those not retained by the Galaxy and will be released.
The club can still choose to sell Ibrahimovic, whose contract at the StubHub Center isn't due to expire until December 2019. He previously spent two years at Milan—the first of which was on loan—and scored 56 times in 85 appearances.
The veteran forward's debut season in MLS was a major individual success. He scored 22 times in 27 league appearances as the team finished one point short of advancing into the Western Conference play-offs.
European interest has followed once more, although the 37-year-old wouldn't reveal much to TMZ Sports in October:
Ibrahimovic was more recently asked by Vanity Fair (h/t MLS Soccer) if he would rejoin the Rossoneri six years after departing but was noncommittal: "I won't say 'no,' and I won't say 'yes.'"
The Italian giants are in need of reinforcements to star striker Gonzalo Higuain, who is their top scorer in Serie A with five goals this term. However, manager Gennaro Gattuso is short on alternatives, and 20-year-old Patrick Cutrone is not yet the finished article.
Gattuso spoke to Sky Sport Italia (h/t AS) and addressed the Ibrahimovic rumours after Saturday's 1-1 draw at Lazio: "We'll see, but I think right now we need to concentrate on what we've got and what we need to do. There's no point thinking about it now. I just have to get my team playing as best we can."
Ibrahimovic sparkled in MLS, but the striker could still be capable in one of Europe's big divisions. Having left Manchester United to move stateside, he recently joked the Premier League wasn't as difficult to master as some might suggest, via BBC Sport:
Leonardo was director of football at Paris Saint-Germain when the frontman moved to France, and the pair could reunite at the San Siro.
However, the Galaxy seemingly intend to fight for their forward's future in Los Angeles in the hope he'll serve a second season on the west coast.