Conor Gallagher has been instrumental for the Eagles this season.
Thomas Tuchel has blocked Gallagher from taking part in the FA Cup semi-final with Crystal Palace.
He has apologised earlier for making him ineligible to play against his parent club.
But Tuchel claims Gallagher will be a part of the Blues when he returns from his loan spell in the summer.
Tuchel said: “I believe Conor can be a part of our squad and can play a role with us. But I am not the only one to decide. We need to speak after the season with everybody, speak after the season about what Conor wants, we need to see what the situation is and what role we have for him that he can fight for.
“There needs to be something to fight, a role and perspective of where you are, where you can be, what you need to achieve. So we have to be very clear with him and he needs to be clear with us.
“He is one of the key players at Crystal Palace and made a huge step in his development up front. He was a pleasure to coach in pre-season – he has so much positive energy, energy in general, and such work rate to give that he can have a big influence.”