Lionel Messi's two-decade stay at Barcelona is over after "financial and structural obstacles" prevented him from signing a new deal, the La Liga club announced.
Barca insist both they and Messi were willing to extend his stay, but claim La Liga regulations have made that impossible.
A statement from the Catalan giants said: "Despite FC Barcelona and Lionel Messi having reached an agreement and the clear intention of both parties to sign a new contract today, this cannot happen because of financial and structural obstacles (Spanish Liga regulations).
"As a result of this situation, Messi shall not be staying on at FC Barcelona. Both parties deeply regret that the wishes of the player and the club will ultimately not be fulfilled.
"FC Barcelona wholeheartedly expresses its gratitude to the player for his contribution to the aggrandisement of the club and wishes him all the very best for the future in his personal and professional life."
Regarded as one of the best to have ever played the game, Messi won four Champions Leagues and 10 La Liga titles at Barcelona. The 34-year-old has won the Ballon D'Or award six times, and is Barcelona's all-time top scorer.
La Liga's tight regulations around team finances, and Barcelona's worsening financial situation due to the Covid-19 pandemic and high wage bill, had left the Catalan club in a difficult situation regarding Messi's contract.
Messi had tried to leave Barcelona in August 2020, making a formal request for an exit after a break down in his relationship with then-president Josep Maria Bartomeu but successor Joan Laporta, who presided over the Argentine's rise to greatness, convinced him to stay
It had appeared Messi would remain at the club earlier this summer, after reports that he would agree a new five-year deal on reduced wages.
It is expected interest in the multi-Ballon D'Or winner will be high, although only a select few clubs in the world will have the finances required to complete such a deal, such as Manchester City and Paris Saint-Germain.
Messi headed to the Nou Camp from his native Argentina, where he had learned his football with Newell's Old Boys, as a 13-year-old in 2000 and progressed swiftly through the club's junior ranks before making his senior debut as a late substitute against Espanyol at the age of 16 in October 2004.
His contribution to the cub since has been stellar with his 778 appearances yielding a staggering 672 goals which have helped to claim 10 league titles, four Champions League crowns and three Club World Cups among his haul of 35 trophies.
Messi told Barca last summer he wanted to leave, with his camp believing he was able to do so on a free transfer, but he remained on board when it emerged he was in fact subject to a €700m buy-out clause during the final year of his existing deal.
Barcelona's money woes
Barcelona have been struggling to reduce their wage bill to be in line with La Liga's FFP rules for the 2021-22 season.
La Liga introduced financial control measures in 2013 establishing a maximum amount of money each club can spend on its playing squad and coaching staff each season, conditioned by their income.
Barca have the highest revenues in world football according to this year's Deloitte Money League, although income dropped by €125m last year due to the impact of the Covid-19 pandemic.
Spanish media reported Barca had been in talks with their top-earning players such as vice-captains Gerard Pique, Sergio Busquets and Sergi Roberto about reducing their salaries by 40% in return for contract extensions.
Barca had also been trying to sell high-earning players, including Antoine Griezmann, Ousmane Dembele, Philippe Coutinho, Samuel Umtiti and Martin Braithwaite, but have not yet found suitors for them.
But the club, along with rivals Real Madrid and Serie A's Juventus, are still clinging on to their plans for the European Super League after a court ruled that governing body UEFA terminate disciplinary proceedings against founding members of the breakaway project.
The Catalan club's president Joan Laporta will hold a news conference on Friday morning in the wake of departure of Messi, who celebrated his first major international title with Argentina last month when they beat rivals Brazil in the Copa America final.
