Arsenal and Real Sociedad are accelerating talks over the transfer of Spain midfielder Mikel Merino to the Premier League club, sources have told ESPN.

The player has already given his approval for the move to go ahead, sources said, but an agreement between the clubs is yet to be reached.

Arsenal's interest in Merino is nothing new. Coach Mikel Arteta has been a fan of the player for some time, and believes his profile -- and evolution in recent seasons -- is what his team needs.

Merino, 28, was part of the Spain team that lifted the Euro 2024 title, contributing most notably with an extra-time winner against Germany in the quarterfinals.

He has twice turned down offers to renew his contract at Real Sociedad, and the Basque club know they must find a destination for him this summer to avoid losing him for free in a year's time.

The size of the transfer fee is the principal obstacle to concluding a deal, sources told ESPN. The LaLiga club expect to receive at least 35 million ($38.6m) for one of their star players, while Arsenal believe that La Real are asking for too much given that Merino's contract expires in 2025.

However La Real rejected a 35m offer for Atletico Madrid earlier this summer, the sources added. The two clubs have a good relationship, however, and there is optimism about reaching a positive solution for all parties.

Sources also said that Real Sociedad are close to agreeing a new contract with Martín Zubimendi after the midfielder turned down a move to Liverpool.

Merino's fellow Spain international Zubimendi decided against a switch to Merseyside this week, and La Real have now taken the opportunity to progress talks over a renewal.

Sources said that an announcement on an new deal that would make Zubimendi La Real's highest paid player, alongside forward Mikel Oyarzabal, is expected next week.