A new era of harmony may have dawned at Stamford Bridge, but sweetness and light did not emanate from José Mourinho last night. While the manager welcomed his recent vote of confidence from the Chelsea board — “I want to stay, they want me to stay, I am staying,” he said — he claimed that Manchester United are being favoured unduly by referees.

While he refrained from using the highly charged word “conspiracy”, the Portuguese pointed to a number of disputed penalty decisions that, in his opinion, signified that Sir Alex Ferguson’s players “are forbidden to lose”. It was an outburst that will further inflame a race for the title in which Chelsea’s goalless draw away to Newcastle United yesterday followed United being held 1-1 at home and leaves the London club still trailing by three points.

After Middlesbrough were denied a last minute-penalty at Old Trafford on Saturday — Sheffield United believed themselves similarly victimised the previous Tuesday — Mourinho made reference to an alleged handball offence by Stephen Carr in the first half. His intervention may draw interest from the Football Association.

“We are fighting for the Premiership even against new football rules,” the manager said. “One rule is that penalties are not allowed against Manchester United and the other is that Chelsea don’t get penalties. With these new football rules, we are doing well and if someone punishes me for speaking the truth, it is the end of democracy.”

The allegations carried a sinister undertone, although Mourinho denied it. “I’m just speaking about facts,” he said, “not conspiracy, so nobody can punish me. It looks as if it’s forbidden to give a penalty against United or in our favour. If anyone tells me it wasn’t a penalty for Sheffield, a penalty for Middlesbrough or one for us against Newcastle, I will go to my optician.”

Yet the tenth-minute incident involving Carr at St James’ Park was not clear-cut and other statistics cast doubt on Mourinho’s contention. United have had three penalties awarded against them at their own ground — albeit in comfortable victories over Wigan Athletic and Bolton Wanderers — while Chelsea have scored from the spot on five occasions this season.

He was more sanguine about Friday’s statement by Peter Kenyon, the Chelsea chief executive, who said that Mourinho would not be dismissed this summer. Roman Abramovich was on Tyneside to witness a disappointing performance, but Mourinho is still to discuss his future with the club’s owner. One element of friction appears to have been resolved, with Mourinho saying that his backroom staff were to be awarded new contracts and that “no” additions were being imposed upon him. “The story is over,” he said. “I have worked with the board for almost three years. It feels good and we’ll work together for the future.”

Watch the Manchester United v Middlesbrough penalty incident here

Watch the Manchester United v Sheffield United penalty incident here

Watch the Newcastle United v Chelsea penalty incident here