Barcelona's 17-year-old defender Pau Cubarsí is being targeted by a handful of Premier League clubs with his release clause set at around 10 million ($10.7m), sources have told ESPN.

Cubarsí only signed his first professional contract with Barça last year, but his emergence in the first team has accelerated the need for the club to agree a new deal with the teenager.

- Stream on ESPN+: LaLiga, Bundesliga, more (U.S.)

Barça were already negotiating an improvement with the centre-back's camp, but sources explain his performances with the first team have "changed the starting point" when it comes to reaching an understanding over a new long-term agreement.

Sources close to the coaching staff detail the maturity and bravery Cubarsí has played with since being handed his debut as a 16-year-old in the Copa del Rey against Unionistas de Salamanca in January.

Cubarsí has since made six appearances under coach Xavi Hernández, including starts in LaLiga wins against Real Betis, Osasuna and Alavés.

"We were joking about him the other day because at just 17 he already seems like a veteran," Xavi said after last weekend's 3-1 win over Alavés.

"He is already playing like a player who is far older than his years. He is aggressive, he does not lose possession and he's so good at bringing the ball out from the back."

Those qualities have led to an urgency to renew Cubarsí's contract as some of England's biggest clubs circle due to his clause being fixed at a relatively affordable 10m.

Cubarsí joined Barça in 2018 as an 11-year-old after spending four years at Girona. He has since progressed through the Catalan club's La Masia academy before he made his Barça Atlétic debut earlier this season as he began to train regularly with the first team.

Xavi handed him his first-team debut on Jan. 19. He has made six appearances since, impressing at the heart of the defence alongside Uruguay international Ronald Araújo.

"He's very well prepared," Xavi said of Cubarsí after he made his LaLiga debut against Betis in January, just days before his 17th birthday.

"He doesn't seem 16 when you speak with him. He is a focused and responsible kid. I don't think he lost a single ball, either.

"He's going to mark an era, the same as Lamine [Yamal] .We are continuing to build a team with young footballers. These are players who we must build the club's future with."

Cubarsí is one of several youngsters to breakthrough under Xavi, with Yamal (16), Hector Fort (17) and Marc Guiu (18) among the others to have made an impact this season.

Fort, who can play across the back four but is primarily a full-back, is close to being signed to Jorge Mendes' agency, sources have told ESPN.