The Swedish centre-back has been linked with a summer departure but Clarke is of firm belief that he will commit to his contract which has one more season with the Baggies.
"There has been no indication that Jonas is going to leave us. Over the summer he's worked well, played games and played with his normal 100 per cent commitment," Clarke told Express and Star.
"He's got a year left on his contract so he's not a free transfer, so as far as we're concerned Jonas is under contract and will be with us next season.
"There is nothing that's happened over pre-season to change our mind on that."