"The chairman has had a meeting with Kanu's agent who said he would come back to us over the next few weeks," Robson told the clubs official website.
"But Kanu is a very doubtful one because of the wages he was on.
"We can't afford those wages in the Championship. That is a fact.
"So it's up to Kanu, whether he's prepared to drop a lot in wages and wants the challenge of staying with the club - or a move elsewhere."