The new deal is a two-year extension to the three-time Ballon d’Or winner’s current contract, which was due to run until June 2016.
Midfielder Xavi Hernández and defender Carles Puyol have also agreed new deals until 2016, the La Liga club confirmed.
A Barcelona statement read: “FC Barcelona can announce that it has reached agreements with Carles Puyol, Xavi Hernández and Leo Messi for the renewal of their respective contracts.
“This news means that FC Barcelona has secured its ties with three of its most important players.
“Over the course of the next few weeks, Carles Puyol, Xavi Hernández and Leo Messi will all be signing their respective new contracts.”
The 25-year-old Messi has enjoyed a record-breaking year for club and country, scoring 90 goals in 2012 and breaking the tally previously set by Gerd Mueller.
The Argentina international has been nominated for a fourth Ballon d’Or award alongside Cristiano Ronaldo and Andrés Iniesta.
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