The 18-year-old is unlikely to stay with the Citizens due to work permit requirements.
Ünal joined City on a four-year deal worth an estimated £2 million on Monday.
The former Bursaspor striker will join City on their pre-season tour in Australia pending his visa. The Turkish intentional is expected to get his visa in time for the senior team’s trip this week.
Ünal holds the record as being the youngest player to ever score in the Süper Lig in 2013 when he netted against Galatasaray.
The City striker has already made his first senior international cap despite being just 18 and netted 24 times in 25 games at U16 level before progressing to the U18 and U21 sides.
The Turkish international was recently listed in the Guardian as one of the 40 best young talents in world football.