The Manchester United manager was open to selling Martial this summer as he was unhappy with the 22-year-olds attitude and wanted the club to sign a more experienced attacker who is capable of playing on the flanks.
But Uniteds executive vice-chairman Ed Woodward vetoed the sale and was adamant that Martial would not be allowed to leave Old Trafford.
United are now in talks to extend Martials contract and have offered the forward a new five-year deal.
Martial has less than a year remaining on his current deal, although United do have the option to extend his contract until 2020.
Woodwards decision to award Martial a new contract appears to undermine Mourinhos authority as United manager.
But according to the Daily Mirror, Mourinho is fully on board with Uniteds decision to extend Martials stay at Old Trafford.
Earlier this week, reports in France claimed that Martial is being used as a pawn in the ongoing disagreement with Mourinho and Woodward.
Martial was dropped from Uniteds matchday squad by Mourinho for the 3-0 defeat to Tottenham on Monday evening.
Mourinho openly criticised Martials performances last season, while he also fined the 22-year-old around £180,000 in the summer after he left Uniteds pre-season tour to attend the birth of his son in Paris and was away from the squad for nine days.
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