Barcelona's Lionel Messi celebrates after he scored a penalty against Valencia during their Spanish first division soccer match at the Mestalla stadium in Valencia, Feb 3, 2013. [Photo/Agencies]

MADRID - World Player of the Year Lionel Messi has signed a new contract with Barcelona which ties him until June 30, 2018, the Spanish league leaders said on Thursday.

The 25-year-old penned a deal agreed in December, which includes a two-year extension on his previous agreement and secures his services until he is 31.

The Argentina captain joined Barcelona's youth academy as a 13-year-old and made his first-team debut at 16.

Messi is Barca's leading scorer of all time, he has been the top scorer in the Champions League for the last four years and racked up a calendar year record 91 goals for club and country in 2012.

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Factbox: Ballon d'Or winner Lionel Messi