Julian Alvarez will stay at River Plate until the end of the season.
The 22-year old forward was signed for a reported £14m fee from River Plate just before the transfer deadline and loaned him back for the remainder of the season.
The Argentinian striker is expected to arrive in England before July and Guardiola wants the player before the pre-season starts.
Guardiola said: “He’s a player that could be with us but right now we have enough players in that position and I don’t like to have many players in several positions.
“The best is for him to stay at River Plate. He’s developed incredibly well in the last years with (coach) Marcelo Gallardo.
“He’s with his mates and in the next pre-season he will be with us. Then after we’ll decide what happens in pre-season.
“I personally – and we – are really pleased to have this talented young player for the next years.”