Celtic boss Neil Lennon has slapped a £25 million price-tag on Victor Wanyama.
Manchester United, Manchester City and Liverpool are all keen on Wanyama, who has rejected a new contract offer this week.
Lennon said: "I've just said he is worth £25m so they can start the bidding at that. I think Victor can play in any company. He is very consistent and you have to look at what he could develop into as well.
"You look at the player he is now and where he could be in two, three, four years' time. He has been a great performer for us, as have many of the players here, but obviously there is a lot of speculation and interest in him.
"He has adapted brilliantly to the British game because I think he is a top player. Eventually, progress is progress and if a huge club came in for him I doubt there is anyone here who would stand in his way and stop the boy fulfilling what he wants to do.
"But, for the time being, he is our player and we're protecting him. We want him here until we feel it is time for him to go and we get an offer we feel befits his talents."