The father of the Manchester City manager raised the prospect last week.
"It doesn't depend on me," Bartomeu replied to Pep's dad, Valenti.
"It was Pep who decided to leave, but the door will always be open for him at Barça."
Speaking with La Repubblica, Bartomeu was also asked about Inter Milan striker Lautaro Martinez.
He added: "That's a trick question. The only thing I can say is that Inter are playing really well and he's not the only one who's impressed me. it's no coincidence they're top of Serie A."