Reports suggest United have already been in contact with the French side over a move for the 16 year old.
“There has to be gratitude shown for all the hard work we have put into his education,” Lens technical director Daniel Leclercq told France Football.
“The players must be aware that they can’t take advantage of our facilities and coaching.
“Darnel will resume with the youth team at Lens. We are even in talks to see him pledge his long-term future here.”
