The Manchester United manager was reluctant to speak about the confrontation outside the dressing rooms that followed City’s 2-1 victory at Old Trafford.
Mourinho reportedly had milk thrown in his direction after objecting to City’s celebrations.
City coach Mikel Arteta is understood to have suffered a cut head in the ensuing row after he was hit by a plastic drinks bottle — although it is not known who threw it.
The Football Association has asked both clubs for their observations on the incident and has given them until Wednesday to respond.
City manager Pep Guardiola said his players did not over-celebrate following the victory, which put them 11 points clear of second-placed United.
But Mourinho, speaking to reporters in Manchester, said: “He says, he says. He says, he says. I am not here to comment on his words.
“The only thing I can say is that for me, it was just a question of diversity. Diversity in behaviour, diversity in education. Just that. And nothing more than that.”
The United manager attempted to divert several questions about the row, insisting that he wanted to focus on Wednesday’s home match against Bournemouth.
“This press conference is pre-Bournemouth, it is not post-Manchester City,” he said. “That was already done.”
He admitted that United were keen to make up for Sunday’s defeat, which ended a 40-match unbeaten run on their own ground.
“When you lose, you probably have a little bit more desire to win,” he said. “Nobody likes to lose once, nobody wants to lose twice.”
But he was adamant that the motivation was only based on wanting to avenge a defeat, and not because it was against City.
“We lost against Chelsea and in the next match we had a little bit extra to try to win. Chelsea lost at the weekend, for sure they are going to have in the next match a little bit more to give. I think it’s something that every club in the world has.”
Mourinho suggested on Sunday that United’s title challenge was “probably” over but said his players will seek every chance to nibble away at the gap.
“We go match after match, one match at a time, try to win the match, try to get the maximum possible points,” he said. “We have the number of points that we have.
“Last season we had seven less or eight less than at this moment. So we have to try. Last season we drew at home against Bournemouth. Now let’s try to do better than we did last season.”
Defender Marcos Rojo is a doubt for Wednesday’s game after suffering a cut to his head during the match against City.