He said: "I don't care if they are on loan or have a 10-year contract. What they have to do is perform well and, most importantly, when they play - make sure the team wins.
"You bring them in to make the squad a little bit stronger and if they are doing well then we would try and sign them permanently.
"But there has been nothing set in stone that if they play a certain number of games that we would have to go down that route. We'll wait and see."