Manchester United youngster JJ Gabriel has travelled to Barcelona as some of Europe's biggest clubs continue to vie for his signature.
The 15-year-old has told United he wants to cancel his registration with immediate effect.
BBC Sport reported on Thursday that Real Madrid have a firm interest in the forward, and Bayern Munich, Paris Saint-Germain and Barcelona are also known to be keen.
It is understood Gabriel left the UK on Thursday and went to France, but is now in Barcelona.
If United hold on to the Londoner's registration, it would stop him moving to another English club until the end of the season.
But if he obtains a European Union passport through either his father - a former Republic of Ireland international - or mother, who has Greek-Cypriot heritage, he could join a club in the EU when he turns 16 on 6 October.
Gabriel has not trained at United since scoring a hat-trick on his Uefa Youth League debut on 10 September. Tournament rules prevent him from playing for a side other than United in this season's competition.
Sources close to Gabriel were furious the club did not register him for their Champions League opener with Sabah FK, which Michael Carrick's side won 4-0.
The United manager was again asked about Gabriel on Friday at his news conference to preview Sunday's Premier League match against Fulham.
"He's a young boy, JJ, and I think it's important we don't play anything out here," he said.
"With the exposure and scrutiny and everything, you've got to be careful and be sensible and think of him as much as anything.
"The situation will work itself out, whatever way it's going to work itself out. Making sure he's OK is the important thing."
Gabriel scored in his first two Premier League 2 outings for United this season but will not be involved against Brentford at Leigh Sports Village on Friday.



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