Kobbie Mainoo is unhappy with the initial terms Manchester United have offered for a new contract amid sudden uncertainty over his future.

Mainoo, 19, is under contract at United until 2027 and the club has the option of an additional year but he has been heavily linked with Chelsea. United sources say they do not want to drive Mainoo out of the club.

Mainoo, Alejandro Garnacho, Rasmus Hojlund and Andre Onana were the only players United regarded as not for sale in the summer but each individual has endured difficulties this season.

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Midfielder Mainoo spent eight weeks on the sidelines with a hamstring injury in October and November after a weary start to the campaign. He has only started in five of head coach Ruben Amorim's 12 games in charge.

Stockport-born Mainoo impressed back in the starting XI in the 2-2 draw with Liverpool at Anfield on Sunday but United's struggles to comply with the Premier League's profitability and sustainability rules could force their hand with academy sales.

Academy players represent a pure profit and the PSR influenced United's decision to sell Scott McTominay to Napoli in August. United also received fees for Mason Greenwood, Willy Kambwala, Hannibal Mejbri, Alvaro Fernandez and Will Fish.

Former United sporting director Dan Ashworth said in September the era of the one-club player was effectively over. "I've seen this written before, I'm not saying anything new.

"The number of players that will be one-club players there for a long, long period of time, I think it's probably changing within the game and that's an unintended consequence of the rules and regulations."

Mainoo signed his existing deal in February 2023 when he was still only 17. He has since cemented his place in the United side with a string of standout performances, scored the winner in the FA Cup final against Manchester City and contributed to England's run to the European Championship final which he started in.

Mainoo is represented by the Stellar agency and renewed his sponsorship with Nike in August.