Manchester United boss Mourinho is under pressure to deliver at Old Trafford with links to Mauricio Pochettino and Zinedine Zidane both resurfacing.
The Red Devils’ nightmare Premier League campaign means they already sit 18 points behind Manchester City.
As a result, speculation has been rife that Manchester United will move on from the Jose Mourinho era should the 55-year-old fail to steer them to a place in the top four.
However, Mendes has now taken the unusual step of releasing a statment, insisting Mourinho was still happy in the job at Old Trafford despite recent results.
“There have been more rumours of Jose Mourinho leaving Manchester United,” said Mendes.
“It’s totally untrue.
“Jose is very happy at the club and the club is very happy with him.
“He has a long-term contract with Manchester United and is fully committed to the club in building a solid winning project.”
Mendes’ decision to release a statement comes as a time where United players past and present are queueing up to blast Mourinho for his side’s poor form.
And pundits have also got in on the act, with Stephen Warnock taking aim at Mourinho’s decision to regularly criticise his players.
“If you’re one of those players being criticised, it’s not a nice thing to hear,” Warnock said.
“So there is going to be an element of not being happy with the manager.
“For me it’s the wrong thing to do to criticise the players publicly, I think you keep that in-house.
“His job is to get the best out of them players it’s to motivate them every day in training, to motivate them going into a game.
“The modern-day manager at this moment in time is the one who encourages his player, puts an arm round when he needs it.
“He must know how to handle them and not publicly criticise them.”