In September the 20-year-old opted to play for England over the Republic of Ireland and has been awaiting clearance from Fifa.
Grealish played for the Republic at under-21s level but turned down a call-up to the senior squad for a friendly against England in June.
Birmingham-born Grealish qualifies for the Republic through his grandparents.
After an impressive first full year for Villa, Grealish has struggled this season, making only 17 appearances and scoring once.
He has been struggling with an ankle problem and has not featured since coming on as a substitute against Manchester City in the FA Cup on 30 January.
Fifa has given Aston Villa midfielder Jack Grealish permission to play for England.