The Nigerian forward has not featured for the Baggies since he tried to orchestrate a move to Queens Park Rangers on deadline day last month without the permission of West Brom.
"Peter is available for selection," Clarke told the club's official website. "We've had a couple of little chats but nothing in-depth and he knows the situation.
"He knows he needs to work hard and he has to be ready for his opportunity when it comes and, for sure, it will come because we only carry a small squad. He has to be ready to go."
The Baggies will take on Sunderland in the Premier League this Saturday.