Mourinho, who succeeded Louis van Gaal in May 2016, initially signed a three-year contract when he took over the reins at Old Trafford.
The 54-year-old enjoyed success in his debut campaign in charge of United, steering them to EFL Cup and Europa League glory.
Reports emerged earlier this week French giants PSG had got in touch to establish whether he would be potentially interested in managing them.
The Portuguese tactician already has close links with PSG’s sporting director Antero Henrique, having previously worked alongside him at Porto.
And The Sun claim that while Mourinho’s camp is not concerned about the PSG interest, sources close to the club are “alarmed” at the way he has been flirting with them.
As far as United’s board is concerned, they believe Mourinho feels he can’t sufficiently compete with Pep Guardiola’s Manchester United, who remain unbeaten in the Premier League this term.
Although Mourinho has been handed nearly £300million since he took over to spend on players, he wants more money to take United to the next level.
Mourinho recently admitted United may not be his last job as a coach, as he said: “What I can say is that I am still a manager with questions, with ambitions, with a desire to do new things and I do not think… I am sure that I will not finish my career here.
The Sun also claim Mourinho could end up battling it out with Antonio Conte for the job as he appears unlikely to be in charge of Chelsea next season.
United resume Premier League duties at home to Newcastle on Saturday November 18.
Published at Wed, 08 Nov 2017 23:15:00 +0000