President Eduard Shevardnadze (search) warned Friday that the round-the-clock opposition protests in the Georgian capital could spark a civil war, and asked that people stay away from a rally scheduled for later in the day.

Shevardnadze's appeal came after opposition leader Mikhail Saakashvili (search) called on all Georgians to join the protesters outside parliament later Friday. The demonstrators want Nov. 2 parliamentary elections declared invalid and say Shevardnadze should resign.

Shevardnadze went on state television to urge people against going to the rally, warning of the consequences if protesters get out of control. The protests have ranged in size from several hundred people to several thousand.

"The present situation of civil confrontation may develop into a civil war," Shevardnadze said. "If the leaders of this action believe that the protesters will behave as they want them to, then they are mistaken. Some people will be drunk, some people will act as provocateurs, and irreparable things may happen."

By 4 p.m., the scheduled start of the protest, about 15,000 people had gathered outside parliament. Riot troops cordoned off the area surrounding Shevardnadze's official residence nearby, preventing anyone from approaching.

Opponents say Shevardnadze has failed to crack down on corruption or fix Georgia's economic problems. The popular anger has been fueled by allegations of widespread fraud during the elections.

Election results, still incomplete, show the pro-government bloc For a New Georgia (search) in the lead, followed by the opposition Revival (search) party, which tends to support the government on key issues. Official results are scheduled to be announced next week.

The protests have become a fixture over the past week, and at times have taken on a circus-like atmosphere. On Thursday, the demonstrators were joined by a group of large puppets of Shevardnadze and several close associates.

Shevardnadze said it would be "irresponsible" for him to step down but repeated that he could in theory resign after parliament convenes.