Milan have confirmed that chief executive Adriano Galliani met Manchester City officials to talk about Kaka "out of courtesy".
Media reports have speculated City, the richest club in the world, bid 100 million euros ($132.5 million) for the 26-year-old.
Milan have fought off sustained interest from Real Madrid in the past while reports said Chelsea offered an amount just less than City last year.
Club president Silvio Berlusconi has added a note of caution this time, though, saying: "I hope he is not for sale."
A smaller club would bite City's hands off if such a sum was offered but Milan would not be forced to sell simply for financial reasons.
That said, the Rossoneri need reinforcements in defence after only finishing fifth in Serie A last season and missing out on a Champions League spot.
They could buy five world class players with 100 million euros.
The on-loan arrival of David Beckham and the purchase of Ronaldinho in the close season, from under the noses of City, show Milan can still attract the best despite recent struggles.
In any case, Milan do have a free, ready made replacement for Kaka. France's Yoann Gourcuff is on loan at Bordeaux from the San Siro and has been in sparkling form.
DARTING RUNS
The 22-year-old scored a stupendous goal in the 4-0 win over Paris Saint Germain at the weekend.
Gourcuff never really got a look in at Milan because of Kaka but the door remains open for a player who will surely improve.
"He is an excellent player," Galliani said. "There will definitely be space for him at Milan."
Another reason Milan might be tempted to sell Kaka is the fact that he has not been as effective this year as last.
He won the Ballon d'Or and FIFA world player in 2007 but lost both titles to Cristiano Ronaldo in 2008.
Injuries dogged Kaka last year and he struggled for consistency, producing his famed darting runs only now and then.
Judging when players are past their peak is always difficult, and at 26 he should be reaching his prime, but big clubs have sold their best players before and prospered.
Manchester United are a good example. Alex Ferguson had no qualms about selling Jaap Stam, Ruud van Nistelrooy and Beckham.
Kaka has not fallen out with Milan. He has said he is committed to the club as long as they have the same goals as he has. It would be a lot easier for Milan to sell if there was tension with the player.
Perhaps Milan will leave it up to Kaka himself, who would have to decide whether choosing City, a club in the bottom half of the Premier League with little history of winning trophies in England nevermind Europe, would be too much of a big gamble.
Milan, Champions League winners in 2007, have a track record of success while City are not guaranteed to prosper despite their vas
