Cristiano Ronaldo is a Manchester United target, admits Louis van Gaal

The former United favourite left the club for Real Madrid in 2009, for a then-record fee of £80m. He has since become the Spanish club's all-time record scorer, but suggestions have persisted that he would be open to returning to Old Trafford.

Ronaldo turns 31 in February, and had an off-key game against Barcelona on Saturday as Real lost 4-0 to their rivals, Kazinform refers to The Guardian .

Van Gaal said of possible future transfer activity: "We are looking at all players, not just Ronaldo. But these players are mostly ungettable. With Ronaldo, let's wait and hope. There is no trainer in the world that doesn't like him."

Ronaldo won three Premier League titles while at United, whom he joined from Sporting Lisbon in 2003, becoming one of Sir Alex Ferguson's most successful signings. He has been Fifa's world player of the year on three occasions.