The Argentine’s current contract with the Championship side is set to expire at the end of the season and Mowbray admits the club can not afford to offer him a suitable deal.
“There’s not a lot we can do about Julio,” said Mowbray. “He was signed when we were in the Premier League and he’s on Premier League money.
“His contract is expiring at a level that is unsustainable for us. I really like him as a footballer and a man. He really buys into the way we want to do things, and his performance level suggests he likes the way we’re trying to do things.
“There’s a perception that he must be old because he’s been around so long, but he only turned 30 a couple of weeks ago. He has a lot of football still to play, and a lot of earning power in the remainder of his career.
“Reluctantly, we have to admit there’s a fair chance that, come the summer, Julio will leave.”