The Catalan club released a statement on Thursday night stating they had reached an agreement with the intention of signing the deal on Thursday.
But with Barca in a massive financial mess, they have blamed the financial and structural “obstacles” in the La Liga regulations for the fact they must now let him depart on a free.
A range of clubs will be interested in bringing in the Argentine superstar, who will now be a free agent for the first time in his career.
Here, Mirror Football looks at six clubs who could be his next destination…
The leading candidate by far considering their financial power over any other candidate is Paris Saint-Germain.
The French giants can offer Messi the chance to play with a squad packed with talent, having added Georginio Wijnaldum, Ginaluigi Donnarumma and Sergio Ramos to their squad this summer.
Messi would make them the clear favourites to win the Champions League, with the chance to reunite with Neymar also on offer.
A reunion with Pep Guardiola is very much on the cards, with the Spaniard being the manager under whom Messi has enjoyed the most success.
The duo won 14 trophies together during their time at Barcelona, turning the side into one of the best in history.
Guardiola could now put his pursuit of Harry Kane to one side to bring in a player who many consider to be one of the best in history.
Where will Lionel Messi move to this summer? Comment below.
City’s Premier League title rivals could also make a play to sign Messi, with their transfer business so far proving they would have the financial muscle.
Though Ole Gunnar Solskjaer would have to change his system in order to fit the Argentine into his side, it would surely be worth it to deny City the chance to sign him.
Though a defensive midfielder is probably more the area they need to strengthen, Messi arriving would make them favourites to lift a first league title since 2013.
The third and final Premier League side who would be able to bring in Messi is Chelsea, who are backed by Roman Abramovich’s billions.
The Blues are currently attempting to sign Romelu Lukaku in a record-breaking move, but could change their focus to Messi.
He would certainly provide the goals that Thomas Tuchel is looking for, having scoring 30 times despite Barca finishing third last season.
Having appointed Max Allegri as manager, the Old Lady can offer Messi the chance to play under one of football’s leading bosses.
Despite a disappointing season last year, they still possess a squad able to fight for the Champions League next year.
Arguably Messi’s least likely destination is the MLS, though reports have surfaced that the Argentine is eyeing a move to America before he retires.
Inter Miami are the MLS side which has been linked the most to a move for Messi, with David Beckham attempting to build a side ready to challenge for trophies.
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