"It would have been possible if the two clubs had reached such an agreement but they haven't and the tight schedule leaves no room for a postponement," Serbian league commissioner Branislav Delic told Reuters by telephone on Friday.
"The match will go ahead as planned on Saturday April 23 because last-minute changes to the competition schedule, which was drawn up last July, are not possible" he said.
"The date is not an official religious holiday and hence organising the derby as planned should not offend anyone's religious beliefs."
With the fixture sandwiched between Easter Friday and Sunday, the Serbian Orthodox Church issued a statement earlier on Friday saying no football should be played on a day its "faithful children spend in prayers and tranquility."
Many Partizan and Red star fans had earlier said on message boards the game should be played the following week and some of them have also threatened to boycott the derby.
But both clubs, whose fixtures have a history of crowd trouble although their three encounters so far this season were played in a good atmosphere, remained in favour of the league calendar.
"As far as we are concerned, the match will go ahead when it's supposed to and we are looking forward to it," Partizan's secretary general Darko Grubor said.
"We are the hosts and therefore in charge of organising the match, so it would be rather awkward to shift the entire event at what would be an unfeasibly short notice."
Red Star spokesman Marko Nikolovski said the 1991 European Cup winners were fully focused on winning their first league title since 2007.
"I don't know what each individual player thinks about the issue, but winning the league is certainly the first thing on their minds and I am sure that none of them will see playing on April 23 as an act of sacrilege," he said.
"We are preparing for the two upcoming games against Metalac Gornji Milanovac and Sloboda Point Sevojno, where we need to take maximum points to stay in the hunt."
Partizan, who are aiming for a record fourth successive league title, are top of the 16-team first division three points ahead of second-placed Red Star.
They are also on course for the domestic double after beating Red Star 2-1 on aggregate to reach the Cup final where they meet Vojvodina Novi Sad on May 11.
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