The Frenchman, who can play at left-back and centre-half, has a £70m release clause in his current contract, which is set to expire
Marca have claimed United are willing to meet the excessive fee for the 2018 World Cup winner.
The 22-year-old revealed recently that he rejected advances from Real this summer, but it is believed he would be willing to listen to other offers.
And United boss Jose Mourinho remains increasingly confident of prising Lucas away from the Spanish capital. It is believed the Red Devils are willing to double the Marseille native's wages.