Manchester United reportedly agreed a £133million (€150million) deal for Ansu Fati last summer with his agent Jorge Mendes but Barcelona didn't sanction the transfer.
United were eager to sign the 18-year-old, who is one of the standout youngsters in world football.
As reported by Sport, United wanted to bring in the winger after failing to secure a deal for Borussia Dortmund's Jadon Sancho.
United attempted to bring in Fati for a significant fee despite their financial problems. They are on course to record losses of nearly £200million during the current campaign.