The teenager is said to favour playing for the country of his birth and has no intention of switching nationality.
According to a report by the Daily Mail, Mainoo is seen as a super professional who will develop into a regular for the Three Lions.
Mainoo made his Premier League debut in Manchester United’s comfortable 3-0 victory against Everton on Sunday.
The 18-year-old put up an assured performance in the middle of the park as goals from Alejandro Garnacho, Marcus Rashford and Anthony Martial helped the Reds to record the win.
Mainoo’s performance has been widely praised by both fans and pundits and some Ghanaians are already dreaming of seeing him in a Black Stars jersey.
Although the young midfielder was born in England and has represented the country at U17, U18 and U19 levels, he’s still eligible to play for Ghana due to his roots.
Meanwhile, Manchester United legends Gary Neville and Roy Keane were full of praise for Mainoo’s performance.
Neville said: "There's an 18-year-old out there who looks more composed than anyone.
"Mainoo has been Manchester United's best player by a street. A brilliant, brilliant Premier League debut from him."
Keane added: "Unbelievable. We don't want to get too carried away but I'm sure we will.
"He looked like he always had time on the ball today, his decision-making, in terms of when to go long when to go short, in terms of off the ball as well. What an all-round performance.”
Mainoo retains the trust of Manchester United manager Erik ten Hag, who gave him his Premier League debut last week.