Manchester City's celebrations after beating Manchester United at Old Trafford were not excessive, their manager Pep Guardiola said on Tuesday.
British media reported that United manager Jose Mourinho was upset by the behaviour of the City players who threw milk and water at him following their 2-1 Premier League victory on Sunday.
Mikel Arteta, part of City's coaching team, was also reported to have suffered a cut in the alleged incidents and the FA has asked both clubs for their observations.
"Everybody fought hard to win," Guardiola told a news conference. "We could have scored more goals. After the game we celebrated with the fans and went to the changing-room and celebrated the win.
"We try to celebrate, because when we lose we try to accept the defeat, but when we win we celebrate. We won a derby, what do people expect we don't celebrate?
"I am the guy who encouraged them to do that, but inside, and after what happened, it happened, hopefully it will not happen again."
Guardiola refused to comment on reports that Mourinho had entered the City dressing-room.
"We just won a derby against our rivals," he said. "When United win a derby they celebrate. When Arsenal win against United they celebrate it."
Mourinho was tight-lipped about what happened in the dressing room during his own news conference ahead of United's home clash against Bournemouth on Wednesday.
"This press conference is pre-Bournemouth, not post-Man City," he said. "That is done."
The United manager did not comment on Guardiola's assertion that City's celebrations were not excessive, but said the behaviour displayed by their opponents after the match was a question of "diversity".
"He says, he says. I'm not here to comment on his words," Mourinho added. "The only thing I can say is for me it's just a question of diversity. Diversity in behaviours, diversity in education. Just that and nothing more than that."
Guardiola's team, 11 points clear at the top of the table, travel to second-bottom Swansea City on Wednesday and will be without captain Vincent Kompany who has a muscular injury.
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