Kenny Jackett has identified Hanlan as the pacy forward who can add an extra dimension to the Blues’ attacking options.
The former Charlton man has spent the past two seasons at Priestfield, scoring 16 goals in 84 appearances.
Despite being out of contract, Hanlan's continued to train with the Gills during pre-season.
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The 23-year-old came off the bench in their 1-0 friendly defeat to Leyton Orient on Saturday and has been offered a new deal to stay at the Gills.
Evans revealed ‘two or three clubs’ have asked about Hanlan – but a compensation fee will first need to be settled before he departs.
The Gillingham boss told his club's website: ‘Brandon Hanlan, two or three clubs have asked about him.
‘We turned good money down for Brandon back in January.
‘Brandon said he'd perhaps like the opportunity to go and talk to these people.
‘They need to agree a fee first otherwise he's not going anywhere.’