The Magpies made a good start to the window by signing Kieran Trippier and Chris Wood, but they want to sign two centre-backs as a priority and have not landed one yet.
They walked away from attempts to sign Sven Botman from Lille after the French club refused to sell and are experiencing difficulties trying to sign Diego Carlos from Sevilla.
While Newcastle are yet to give up on Carlos, the Sevilla defender has indicated that he is likely to stay at the Spanish club beyond the 31st January deadline.
There are claims that Sevilla would sell if Newcastle double their current offer but the Magpies do not want to overpay for players.
Newcastle are aware that clubs are putting up their asking prices because of their status of the richest club in the world.
But they do not want to make the mistake of setting a precedent by paying over the odds for players.
Newcastle have big plans for the summer if they survive in the Premier League and are aware asking prices for their targets will go up if they overpay now this month.
The Magpies want to comply with the Financial Fair Play Rules by keeping their spending at a certain level.
However, Newcastle are not shying away from offering massive wages to their targets in order to tempt them into pushing for a move.
