The Wales international has asked to leave Real Madrid, while the Old Trafford side have rekindled their interest ahead of the summer transfer window.
Manchester United are preparing a €120 million offer for Gareth Bale, according to El Confidencial.
It has been claimed that the Wales international is keen on a return to the Premier League, while United have reignited their interest.
Bale has asked Madrid president Florentino Perez if he can leave the club this summer, but the forward has a contract until 2019 and will command a huge fee.
The 26-year-old, who arrived from Tottenham in a world-record €100m deal, has spent three years in Spain and has won the Champions League twice.