Spanish newspaper El Pais made the publication on Friday, revealing the four-year contract extension Messi signed in 2017 entitles him to leave the Camp Nou in 2020.
Some of Europe’s biggest clubs will be salivating at the prospect of getting arguably the best footballer the world has ever seen into their fold, especially when it involves no transfer fee, but Bartomeu is not entirely troubled about the situation.
Bartomeu revealed the likes Carles Puyol, Andres Iniesta and Xavi Hernandez all had similar clauses inserted into their contracts but they played their best football at the Camp Nou and he expects Messi to follow the footsteps of his fellow La Masia academy graduates.
“Messi has a contract that we signed two years ago and it runs for four years," Bartomeu told Barcelona's website.
"Before the last season, 2020-21, he can leave Barcelona, retire from football or play where he likes.
"Iniesta, Xavi and Puyol also had those clauses. For those players and Leo Messi, we don't need to worry.
"I doubt he'd want to play for another club, but he has earned liberty over his future. He's a big Barca fan and I have no doubt he'll want to continue until 2021 and we hope another year too."
Barcelona have made an inauspicious start to the season without an injured Lionel Messi, picking up just four points from their first three league games, but they expect an upturn in fortunes when the five-time Ballon d’or winner returns to action after the international break.