Two Russian planes evacuated approximately 80 embassy personnel and family members from Georgia on Friday, an embassy official said, as a spying row deepened and Western defense ministers called for calm.
Moscow ordered the partial evacuation after Georgia arrested four Russian officers and accused them of spying on military installations in the strategic Caucasus country.
A Tbilisi court on Friday ordered that the arrested officers be detained for a further two months pending investigation, Georgia's Rustavi 2 television reported, although prosecutors confirmed the measure against only two.
But Defense Minister Irakli Okruashvili said he did not rule out returning the four to Moscow.
"There have already been similar precedents in international practice when foreign citizens without diplomatic status and held in a similar situation have been expelled from the country," he said on Georgian television channel Imedi.
Russia angrily denounced the officers' arrests, called for their release and urged the UN Security Council to take action to restrain Georgia.
The US urged Russia and Georgia to find a diplomatic solution to the dispute, while the State Department rejected the Russian call for the issue to be taken up by the Security Council, with spokesman Sean McCormack saying "it's an issue that is best and most properly resolved between two neighbors."
"On both sides, we would just urge them to put the events in the proper context," McCormack said, adding that Washington had been having "diplomatic contacts" with both governments.
Russia's envoy to the UN, Vitaly Churkin, accused Georgia of "serious provocations," while Foreign Minister Sergei Lavrov complained on Thursday that "the party of war" was getting the upper hand in Tbilisi.
Russian embassy spokesman Mikhail Svirin said that the evacuation was justified as the "security threat is credible."
Arriving for consultations in Moscow, Russia's ambassador to Tbilisi, Vyacheslav Kovalenko, said further personnel would be evacuated from a military base on the Black Sea coast at Batumi, the ITAR-TASS news agency said.
Saakashvili denied there was any threat to Russian personnel, saying "there are no kind of threats to the security of Russian families in Georgia as our country acts strictly in accordance with international agreements."
Saakashvili held phone conversations on the situation with US Secretary of State Condoleezza Rice and the chairman-in-office of the Organization for Security and Cooperation in Europe (OSCE), Karel De Gucht, his press office said.
Georgian Interior Minister Vano Merabishvili said that Russia was stepping up military activity near the sea border and accused Moscow of "saber-rattling."
Relations between Russia and the ex-Soviet state have been tense at various times for two centuries.
They have worsened significantly since 2003, when the Rose Revolution swept US-educated Saakashvili to power in Tbilisi and he vowed to lead Georgia away from Russian influence and towards the West.
Meeting in Slovenia on Friday, NATO ministers called on Russia and Georgia to calm tensions.
NATO Secretary-General Jaap de Hoop Scheffer "called for moderation and de-escalation [on the part of] all partners" after a meeting that was also attended by Russian Defense Minister Sergei Ivanov.
US Defense Secretary Donald Rumsfeld echoed the call for calm, saying the confrontation was "a subject of concern."