Celtic manager Ronny Deila insists Virgil van Dijk does not want to leave the Scottish Premiership leaders in January.
Celtic boss Ronny Deila says keeping his best players will take priority over acquisitions in the transfer window.
Luuk de Jong could be set for a January loan move from Borussia Monchengladbach, which could reignite interest from Newcastle United.
Newcastle tried to sign the Dutch international from FC Twente before he opted for a move to Gladbach in 2012 for more than £12million.
The 23-year-old is now set to be made available for loan having failed to start a league game this season, and it is understood Newcastle are monitoring the situation.
Borussia board member Hans Meyer has suggested that De Jong could be allowed to leave by saying: "We will possibly loan Luuk at Christmas but definitely not to a competitor.
"Our head coach Lucien Favre has said from the start he didn't have 100% confidence in De Jong filling the striker position but I think we'll find a solution."
However, their sporting director Max Eberl was quick to reply and seemed to down play the chances, adding: "From our side, this question has absolutely not been raised.
"It's a difficult situation for Luuk, but we are just as happy to have him first in our squad as other clubs would be when they have such a player."
De Jong himself said: "I want to play for Borussia, that's my goal. If the team needs me, I'm ready. I want to play from the first minute onwards."
As well as De Jong, Newcastle are also keeping tabs on Lyon striker Bafetimbi Gomis - another player they failed to land as a deal fell through for him this summer.
The 28-year-old is out of contract at the end of the season and a move to Italy has been mooted - but Gomis appears to be standing by his stance of going on a free transfer.
"I have made it clear, I want to leave Lyon at the end of the season," Gomis said.
"This club has been great to me since I joined from St Etienne, yes the last few months has been a bit difficult but I want to help the club finish strongly this season which would also give me a chance to go to the World Cup.
"If I move to a new club my chance will be more difficult, I want to go at the end of the season."