Isak made 39 appearances in all competitions for Los Txuri-Urdin during the 2021/22 season, scoring ten goals and laying on three assists, a far cry from his numbers from the previous campaign that resulted in links with the likes of Barcelona.
Newcastle are keen on the Sweden international, but are claimed to be looking for at least £50m to let him go, a sum which is too high for the Magpies.
Real Sociedad have not denied holding talks with Newcastle about Isak, but insist he is due back at training on Thursday as they prepare for the new season.
It is suggested that the Spanish side are currently pricing the striker too high for Newcastle to pursue.
The Magpies are on the hunt for another goalscorer after last season’s top scorer, with eight goals, Callum Wilson missed half of the Premier League campaign through injury.
Newcastle spent most of the first half of last season in the relegation places but managed to finish as high as eleventh in the Premier League table.
Having spent heavily in January following the Saudi-backed takeover to ensure their Premier League survival, the Magpies have spent conservatively thus far this summer, having made Matt Targett’s loan permanent and added Nick Pope and Sven Botman to their ranks.
Newcastle want to add another centre-forward and a wide player to the squad, given the uncertainty surrounding the future of Miguel Almiron, before the transfer window closes.