There has as yet been no agreement to turn the Argentinian striker's loan spell into a permanent deal and he has revealed he would like a move to Spain.
He told Madrid's Cadena COPE radio station: "Yes it's true I see myself more leaving United than staying here. I don't see why I should lie to people or anything because the fans support me a lot, as you can see. So I don't have any reason to lie to them."
He added: "While I wear the United shirt, I will leave my life on the pitch. My future? I don't know what will happen for my future. I would like to go to Spain, yes, but I don't know yet. I have no preference for a team.
"With respect to the fans and the history of Manchester United, I don't want to leave the club. But, from a personal aspect, my exit will be the best solution.
"I need continuity in the team to offer my best. If this doesn't happen I believe this will be my last year."