The 37-year-old Argentina captain has not played since suffering ankle ligament damage during the Albiceleste's 1-0 victory over Colombia in the Copa America final in July.
But he has returned to full training and will almost certainly be called upon for Inter Miami's home clash against Philadelphia on Saturday, reported Xinhua.
"Yes, he's fine," Inter Miami manager Gerardo Martino told reporters on Friday.
"He trained [on Thursday] and he's in our plans for the match. After training today we'll think about the strategy for him, but he's available."
Messi has 12 goals and 13 assists in 12 MLS appearances this season.
Martino was unperturbed by the eight-time Ballon d'Or winner's lack of match fitness, saying his mere presence would provide a major boost to the Florida outfit.
"Welcoming back the best player in the world for our team, which was already on a good run, makes us all very happy," Martino said.
Inter Miami currently lead Major League Soccer's Eastern Conference standings with 59 points from 27 matches, eight points clear of second-placed Cincinnati.
