But Clarke admitted there is a buy-out clause in Olsson's contract which could be activated this summer by one of six clubs he has stipulated in his terms.
Clarke claims Olsson is happy to remain with the Baggies - at least in the short term - after reports that he is keen to be based in London for family reasons.
The former Chelsea number two said he will not welcome any new bids for the 29-year-old player during the remainder of the current transfer window.
Clarke said: "I can confirm a bid has been turned down and I don't encourage anymore bids because Jonas is not sale.
"I have spoken to Jonas and he says he is loving the football here and is looking forward to the rest of the season.
"He will remain a West Brom player and we don't have to sell anyone.
"He is not for sale so there is no figure which is reasonable."
But when asked if there is a buy-out clause, Clarke said: "There is a clause in Jonas' contract which comes into play during the summer.
"There are six clubs that can invoke that."