Manchester United boss Jose Mourinho has conceded that he is "not confident" David de Gea will sign a new long-term contract with the 20-time English champions.

De Gea's current deal with United will expire at the end of this season, and despite the Red Devils having the option of a 12-month extension, there remains huge uncertainty surrounding the Spaniard's future.

The 27-year-old is believed to be weighing up his future at Old Trafford, with United currently struggling to challenge for the major trophies.

Mourinho is reportedly fearful of losing the Spaniard on a free transfer to Juventus, and the Red Devils boss has now conceded that his number one could move on.

"I am not confident," Mourinho told told Sky Sports News. "I cannot find the word in English, but let's see what happens. Only the club, David and his people can answer that.

"My comment is only that everyone knows how good he is, how important he is for Manchester United and, if the club want to be better than it is and not worse, obviously it would be very important to keep David."

De Gea has made 327 appearances in all competitions for United since a 2011 move from Atletico Madrid, winning one Premier League title, the FA Cup and the League Cup during his time at the club.