The 29-year-old was close to inking a deal with UAE side Al-Nasr this week only to see the transfer collapse at the last minute.
The Rossoneri are looking to strengthen their attack with the losses of Giampaolo Pazzini and Robinho due to injury and according to Sport Mediaset, the Argentinian born striker could provide the ideal cover on a short-term basis.
This would be his second spell with Milan, having spent six months on loan there during the second half of the 2011-2012 season and netted twice in 11 appearances.
However, the Rossoneri decided not to purchase him outright and he returned to Catania. He was then once again sent out on loan, this time, to Sampdoria, where despite scoring five times in 18 matches, he again returned to the Sicilian-based club at the end of last season.
Since making his professional debut with Argentinian side River Plate in 2001, Lopez has played for the likes of Barcelona and Mallorca as well as now defunct Russian side FC Moscow before making his Serie A debut with Catania in January 2010.
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