Manchester United boss Louis van Gaal says he does not want Luke Shaw to play for England at this summer's European Under-21 Championship.
Full-back Shaw, who joined United from Southampton last June, has missed much of this season because of injuries.
Van Gaal said: "When you are not playing for Man Utd you cannot play for other teams. He needs the rest.
"He is 19. We have to protect him. I hope that the coach of the Under-21s understands that."
Shaw has started just 18 games for United since joining them for £27m last summer, as ankle and hamstring injuries disrupted his maiden campaign with the club.
He will miss United's match with Arsenal on Sunday after receiving an elbow to the face in the win at Crystal Palace last weekend.
The left-back's fitness was also questioned by Van Gaal during pre-season.
Van Gaal's comments put further doubt on the prospect of England Under-21 manager Gareth Southgate being able to select a full-strength squad for this summer's tournament, to be held in the Czech Republic between 17-30 June.
Tottenham striker Harry Kane, who scored on his senior England debut, could feature for the U21s but Spurs have arranged a friendly in Australia less than three weeks before England's first game against Portugal on 18 June.
Everton manager Roberto Martinez said recently that midfielder Ross Barkley would need a "proper break" in the summer, while Southgate has previously said he is "not convinced another tournament in the summer would be right" for Liverpool winger Raheem Sterling, who played for England in the 2014 World Cup.
However, in March, Southgate, whose side qualified for the finals without losing a match, said he does not expect Premier League clubs to oppose the release of players, adding: "We've looked after the players physically, and that helps us in terms of their release."
England's last appearance at the tournament in 2013 ended with Stuart Pearce's side exiting from the group stage having lost all three of their matches.