Javi Martinez has penned a new deal with Athletic Bilbao.

Martinez has signed a two-year contract extension with the Primera Division outfit, the club have confirmed on their website.

The highly-rated 22-year-old, who was part of Spain's World Cup-winning squad last summer, is now tied to the Basque giants until June 30, 2016.

The buy-out clause in Martinez's new contract is 40 million euros.