Arsenal have reportedly been told that they will have to pay over £50m to sign Real Sociedad's Martin Zubimendi.
Mikel Arteta is keen to add a midfielder before the January transfer window ends, as the Gunners seek to maintain their five-point lead at the summit of the Premier League.
The Times reports that the Spanish club have told the Arsenal that they will have to pay his full release clause if he is to leave this month.
That release clause sits at £52.8m, as the midfielder only signed a new contract three months ago, and Sociedad are confident of keeping the 23-year-old at least until the end of the season.
The Basque club currently sit third in La Liga, seven points ahead of Atletico Madrid, who occupy the final Champions League qualification spot.
The midfielder has featured 23 times so far this season in all competitions, scoring one and assisting three goals.