The 23-year-old is set to leave the Bernabeu this summer after an impressive loan spell with Sevilla last term and United had been in negotiations with Madrid for the last week over a £20m deal.
However, talks hit a stumbling block when Madrid insisted on a buy-back clause, with United unwilling to agree.
That’s opened the door for Tottenham and the Athletic claim that a deal is close to being struck that will see the Spaniard move to North London on a permanent basis.
Spurs have signed Matt Doherty and Pierre-Emile Højbjerg so far this term but Jose Mourinho is keen on signing a new left-back after Danny Rose was given permission to leave the club.
Solskjaer had been keen on signing competition for Luke Shaw, who missed around four months of the season last term through injury.
However, Reguilon spoke with Mourinho in early September and convinced the Spaniard to join Spurs.
Zidane worked with Reguilon when he was head coach of Real Madrid’s youth side, Castilla but the Frenchman is not convinced that the defender has what it takes to succeed at the Bernabeu and has informed him that he’s surplus to requirements.