"The Russian side... stressed the inadmissibility of setting time limitations on the negotiating process," Sergei Lavrov said at a meeting with Wolfgang Ischinger, the European Union's representative at talks on the status of Serbia's breakaway province.
World powers have given Belgrade and Pristina a deadline of December 10 to reach agreement on the issue.
Kosovo, now 90% populated by ethnic Albanians, has been a UN protectorate since NATO's 1999 bombing campaign that ended a conflict between Serb troops and Albanian separatists. Serbia has offered Kosovo broad autonomy, but Kosovo Albanians are insisting on full sovereignty.
In late September Serbia and Kosovo held their first round of face-to-face talks, in the presence of international mediators, but failed to reach any agreement. The sides merely confirmed their commitment to refrain from actions that could undermine security.
Ischinger said after the discussions that a second round of direct talks between Serbs and Kosovo Albanians, mediated by Russia, the U.S. and the EU, would be held in Brussels on October 14.
Russian President Vladimir Putin also said earlier that Russia is against setting time limits on dialogue between Belgrade and Pristina.
However, the U.S. has made it clear that it will recognize Kosovo's independence after the December 10 deadline if no agreement is reached.
Russia, a veto-wielding Security Council member and a staunch ally of Belgrade, has repeatedly said that granting Kosovo sovereignty would violate Serbia's territorial integrity and set a precedent for other breakaway regions, including those of the former Soviet Union.
