Manchester United are reportedly demanding around €10m from Real Sociedad for Belgium playmaker Adnan Januzaj.
Januzaj, 22, was heavily linked with a move to Real Sociedad in 2015 when David Moyes was the manager of the Basque side.
The Belgian had previously enjoyed an impressive breakthrough campaign at United under the Scottish manager, netting four times in 27 Premier League appearances during the 2013-2014 season.
Nevertheless, Januzaj has since failed to fulfill his potential in successive campaigns.
Januzaj was sent him on loan to Borussia Dortmund in the summer of 2015 before recalling him mid-way through the campaign after failing to secure regular time at the Bundesliga side.
Mourinho said last summer that Januzaj featured in his long-term plans but dispatched him to Sunderland with the hope he could resurrect his career under Moyes.
"He fits in my plans which is why he's on loan at a Premier League club," Mourinho then said. "If he didn't fit into my plans then we don't care about where he's going. We care about him and think he's a talented player.
"I want to give him all the conditions to develop and to play well. He is in the right place with a manager that likes him a lot. Hopefully everything will go well for him because we want him back!"
However, Januzaj also failed to make the impact expected at the Black Cats and Marca claims that Manchester United are now likely to sanction his departure on permanent basis.
