After the World Cup, Celtic plan to make a transfer offer in January for Josip Juranovic.
The Croatian right-back will compete in the Qatar tournament.
According to recent reports, a host of big European clubs have expressed interest in the 27-year-old after his consistent and impressive performances in a Celtic shirt.
Atlético de Madrid, Manchester United and Chelsea have expressed interest.
According to the Daily Mail, Celtic are bracing for more interest after the World Cup.
They claim that talks over a new contract at Parkhead have stalled.
The Croatian’s current deal runs through 20216, so he will still command a hefty fee if a team wants to buy him.
He joined in the summer of 2021 from Legia Warsaw for a fee believed to be around £2.5m.
Ange Postecoglou recently spoke about the sale of players and its importance.
He said: “If our players do well and move to the so-called greener pastures, if that’s what they want, then I have a chance to improve the team.
“Because if they’re going to let us, we’re going to make some money. I’m not worried about losing our players. That, in my opinion, is part of the process.
“What do clubs our size do when they perform well in the Champions League?
“They create players, sell them, and hopefully replace them with better versions. That’s where I think we’ll grow.’ I think it’s a natural part of the process. I’m not afraid. That, I believe, is necessary for us to progress. We need to bring money to continue bringing better players”.