The municipal court president Dragoljub Jankovic, clarifying the effect of appeals against the electoral panel's decision, said it was put on ice pending a ruling by the Supreme Court on which court should decide the volatile issue.
The opposition Zajedno (Together) coalition has staged nine weeks of street protests against the annulment of its victories in countrywide municipal elections, generating pressure in the West for democratic reform in Serbia.
Analysts said the Socialist- influenced municipal court may have been browbeaten by party bosses into passing the buck to higher legal organs under no deadline for a ruling, giving hardliners more time for counter-moves.
Zajedno fears a new outbreak of political violence in Serbia's Albanian- majority pro- vince of Kosovo could allow Mr Milosevic to divert attention from the election crisis and build a case for emergency measures to quell any dissent.
Belgrade's multi-party electoral commission reinstated Zajedno's triumph in the capital a week ago but said its judgment was preliminary and open to appeals.
Jankovic said two appeals were submitted - one by the Socialists (SPS) and the other by the rightist Serbian Radical Party (SRS), which is not in the government but opposes Serbia's moderate opposition bloc.
"The decision of the electoral commission is suspended until the Supreme Court decides [which court should rule on the matter]," Mr Jankovic said.
He said the Supreme Court had no deadline for a ruling. Officials in Nis, Serbia's second city, declared a Zajedno victory last week. The SPS lodged an appeal but it was thrown out by Nis municipal court. Zajedno plans to convene the new regional assembly on 27 January.