The 34-year-old – who was a part of Jose Mourinho’s Champions League-winning squad at the San Siro in 2010 – is set to be out of contract at the end of the season, and looks unlikely to be offered an extension by the Serie A giants.
This has opened up the opportunity for a winter swoop, which has alerted Allardyce.
‘Big Sam’ is desperate to bolster his attacking line next month after spending the majority of the opening months of the season with only Modibo Maiga available as a central striker thanks to Andy Carroll’s fitness concerns.
Milito would bring a wealth of experience having enjoyed successful spells in his homeland, Spain and Italy, as well as numerous campaigns in continental competition.
It remains unclear as to whether the veteran forward will be tempted by a move to Upton Park, but the lure of Premier League football may be enough to convince him to join the Hammers.
Allardyce is also monitoring Tottenham outcast Emmanuel Adebayor and Demba Ba of Chelsea – both of whom may be available on loan.