Newcastle started out the January transfer window looking to bring in two centre-backs, but they have yet to get one in through the door.
That is expected to change due to having agreed a fee with Brighton for Dan Burn, who has travelled to the north east to complete the switch.
They have also been linked with putting a bid in for West Ham defender Diop, which is expected to be rejected.
However, it has been claimed that Newcastle may have Diop just as a backup option in the event that something derails Burn’s move to St James’ Park.
Newcastle are busy as the transfer window enters its final stretch, with deals on the go for several targets.
They are moving to bring in left-back Matty Targett from Aston Villa on an initial loan, while also trying to sign Hugo Ekitike from Reims.
Brazil international midfielder Bruno Guimaraes completed a move to Newcastle from Lyon over the weekend.
