However, any move for the 27-year-old is dependent upon Milan's pursuit of Carlos Tevez.
The Rossoneri are keen to sign the Manchester City centre-forward, although they are yet to reach an agreement with the Premier League leaders.
"There is an agreement with Catania: if Tevez won't come, Maxi Lopez arrives," said AC Milan chief executive Adriano Galliani.
"Now let's see what happens, we'll wait a few more days. Maxi Lopez is a player who interests us very much, we already agree with everything and therefore he is very likely to arrive.
"The desire of Tevez to come to AC Milan is very pleasing, and we also want him to arrive. Let's see."
Lopez joined Catania in 2010 from Russian club FC Moscow.