Isak handed in a transfer request a fortnight ago, which was followed up by a £110m offer from Liverpool just days later - an offer which was rejected by Newcastle's board.
The Swede has since been training away from manager Eddie Howe's senior squad and has not been considered for preseason selection.
However, the Telegraph is reporting today that Isak's agents were informed by Newcastle this morning that no offer will be considered for the centre-forward before this transfer window shuts at the end of the month.
The board has also instructed Howe to fix relations with the player and bring him back into the fold.
Isak still has a three-year contract remaining and Newcastle have offered him a new deal with the inclusion of a release clause. But the behavior of the 25-year-old Swede's entourage has infuriated Newcastle's management, blaming agents for the "poor advice" they've given Isak.
Newcastle have also let it be known of their resentment over Liverpool's "lower" offer, considering the Magpies ' asking price of £150m.
For the moment, Isak will be registered by Newcastle as their Premier League player for the new season.