Marko Grujić is free to play for Liverpool after receiving his UK work permit.
The 20-year-old Serbian midfielder initially signed with the Reds from Red Star Belgrade in January but spent the remainder of the season on loan with his boyhood club.
Liverpool have confirmed that Grujić has now been granted a work permit and is now eligible to play professionally for the Merseyside club.
Grujić, who will wear the number 16 shirt for the Reds, started pre-season with the rest of the available squad members on Monday after helping Red Star take out the Serbian SuperLiga title last season.