Barcelona, March 10 (IANS): FC Barcelona director of sport Ariedo Braida said that the club could have problems retaining star striker Lionel Messi.

The 27-year-old Messi has spent his entire career at the club and has a contract until June 2019 with a massive buy out clause of around $320 million. But according to Braida, the club can never rule out a surprise regarding his future, reports Xinhua.

"I believe it's very difficult that Messi will leave Barcelona but at times in football strange things happen," he said on Monday.

Braida, who recently replaced Andoni Zubizarreta, explained that the increased amount of money in the game through TV deals and billionaire owners made that clause appear more accessible than in the past.

"Now with these clubs that have so much money like (Manchester) City, certain amounts don't seem to have a value. In football things happen that appear impossible but I hope he will remain," he said.

This is the latest in a chapter of comments about Messi's future. Earlier this year the striker insisted he was happy at the club and has returned to his best form in 2015, highlighted by his hat-trick against Rayo Vallecano on Sunday which took him level on the goalscoring chart alongside Cristiano Ronaldo.