Manchester United star Paul Pogba is "unhappy" at Manchester United and should leave in the next transfer window, his agent Mino Raiola said in an interview with Italian media.

The French midfielder of Guinean descent was at one point the world's most expensive player.

Raiola said the World Cup-winning France midfielder, 27, needs a "change of scene" after struggling to establish himself under United manager Ole Gunnar Solskjaer.

"Paul's unhappy at Manchester United, he can't express himself any more as he would like to and as we expect of him," Raiola told Italian newspaper Tuttosport.

He has to change teams, he needs a change of scene. His contract is up in a year-and-a-half, in the summer of 2022, but I think the best solution for all sides is a transfer in the next window."

Pogba returned from a spell at Juventus for a then world-record fee of $118 million in 2016.

"The club... knows it risks losing him for nothing, as at the moment the player has no intention of extending his contract," Raiola said.

It is not known where he will go next but Pogba has also expressed his desire to play for Real Madrid one day, particularly if that means playing under the orders of Zinedine Zidane.

The midfielder's superb strike in Saturday's 3-1 win over West Ham was his first goal in eight Premier League appearances this season.