The Belgium forward is on a season-long loan at The Hawthorns and has already netted five times, helping Albion climb into the Premier League top four.
However, Benitez admitted he will analyse the situation in a couple more games before making a decision on the 19-year-old.
But the news will worry Clarke, who will be without Peter Odemwingie with the striker set to play for Nigeria at the African Nations Cup in January, meaning he will be short of options.
Clarke said: "It's a situation I cannot control, but I can't spend my time worrying about it.
"It won't be a problem. We know the possibilities that could happen in January and we know what we will do if that happens.
"I'm not telling you my plans. But I have to manage a football club with the help of my staff and scouts.
"We have six scouts having a planning meeting about potential targets and you have to think ahead.
"January's a window and there's one in the summer, so you plan towards those windows and for a number of circumstances that may happen."