The former Tottenham midfielder has been instrumental for the Spanish giants since joining the club in 2012.
Modric, 32, has won La Liga and the Copa del Rey, while also lifting three Champions League trophies.
However, according to Spanish transfer outlet Don Balon, Modric is unsure whether his future lies at the Bernabeu.
They say the Croatia international wants guarantees from Zinedine Zidane that he’s in his long-term plans at Real.
If the Frenchman tells Modric he will become a bit-part player, he’s willing to quit the club.
Don Balon add that Modric has three offers to leave the La Liga champions.
United, PSG and Juventus have all asked about the midfielder’s situation under Zidane.