Georgia's president called Russia "an enemy and occupier" and suggested Moscow had helped trigger protests that rocked Tbilisi, but the Kremlin on Friday blamed radical Georgian politicians for what it called "an anti-Russian provocation."
The strong statement from President Salome Zurabishvili followed violent scenes in the Georgian capital, where police late on Thursday used tear gas and fired rubber bullets to stop crowds angered by the visit of a Russian lawmaker from storming the parliament building.
Hundreds of people, both protesters and police officers, were injured in the clashes, some of them seriously, as demonstrators pushed against lines of riot police, threw bottles and stones, and grabbed riot shields, drawing a tough response.
The speaker of parliament, Irakli Kobakhidze, resigned on Friday, satisfying one of the protesters' demands.
"Russia is our enemy and occupier. The fifth column it manages may be more dangerous than open aggression," Ms. Zurabishvili posted on her Facebook page after the unrest.
"Only Russia benefits from a split in the country and society and internal confrontation, and it's the most powerful weapon today."
Russian influence in Georgia remains a politically sensitive subject, with the opposition accusing the ruling Georgian Dream party – which backed Ms. Zurabishvili for the presidency late last year – of being too meek when it comes to confronting Moscow.
The small south Caucasus nation, a U.S. ally, fought and lost a short war against Moscow in 2008. The two countries have not had diplomatic ties since, and Russia went on to recognize the independence of two breakaway Georgian regions, South Ossetia and Abkhazia, where Russian troops are now garrisoned.
The crowds were angry about the visit of a Russian delegation led by Sergei Gavrilov, a member of Russia's lower house of parliament, who was taking part in an event designed to foster relations between Orthodox Christian lawmakers.
Mr. Gavrilov addressed delegates in his native Russian from the Georgian parliamentary speaker's seat, angering some Georgian politicians and citizens who want Russia kept at arm's length.
Mr. Gavrilov told a Moscow news conference on Friday he believed the protests had been pre-planned.
"Our common view is that there's an obvious attempt in Georgia right now to stage a coup d'etat and that extremist forces are trying to seize power," he said.
Kremlin spokesman Dmitry Peskov said the safety of Mr. Gavrilov and other members of the Russian delegation had been endangered, and he said Moscow was seriously concerned given how popular Georgia remains with Russian tourists.
"Everything that happened yesterday in Georgia is nothing other than an anti-Russian provocation," said Mr. Peskov.
Georgia, crisscrossed by energy pipelines, hopes one day to join the European Union and NATO, an ambition which has infuriated Moscow, the country's former Soviet overlord.
Ms. Zurabishvili, who was visiting Belarus, planned to cut short her official visit there due to events at home, her spokeswoman told Reuters.
The opposition, which has seized on the furore to press much wider and unrelated demands, called on people to take to the streets again on Friday evening at 7 p.m. local time.
Opposition MPs have demanded that the interior minister and state security service chief also resign over the incident.
A Reuters witness said that Tbilisi's main thoroughfare, Rustaveli Avenue, which runs in front of parliament, was closed to traffic on Friday and that the building itself was heavily guarded by police.
This story was reported by Reuters. Additional reporting by Reuters' Tom Balmforth and Maria Kiselyova in Moscow.