Jonah Hull, Al Jazeera's correspondent in Tbilisi, said: "One suspects that there is unfinished business here for the Russians.
"One of their main motivations has been to see the back of Saakashvili [Georgia's president], Putin's long-time nemesis.
"It [the delay in withdrawing troops] is aimed at intimidating him and destabilising the country," Hull said.
On Monday Russia announced the start of its withdrawal from Georgia, but Tbilisi accused Moscow of stalling and seeking to spread further into the country.
Russian soldiers were still preventing access into Gori, just 60km west of Tbilisi.
Four tanks were also present at the checkpoint, an AFP correspondent reported.
"I really do not know how long we will be staying here," said one of the soldiers, who declined to give his name.
The Russian soldiers were bearing the insignia of "peacekeepers" on their uniforms.
Tanks were also in evidence on the road to Gori from Igoeti, 30km west of Tbilisi.
Maxime Verhagen, the Netherland's foreign minister, said ahead of the talks in Brussels that there was disproportionate use of violence by Russia.
"We should send a signal that that the agreement between Russia and Georgia should be fulfilled and the Russian troops should withdraw. But I am also convinced we should have the possibility for dialogue," he told Al Jazeera.
Hannah Belcher, reporting for Al Jazeera from Georgia, said orders to pull out don't appear to have reached the Russian military patrolling the strategic east-west highyway near the city of Gori.
"Their [troops] only movement has been towards the Georgian capital Tbilisi," she said.
"The Russians are expected to be sent a strong message from Nato foreign ministers meeting in Brussels. Nato is set to back Georgia's territorial integrity and condemn Russia's military presence."
She said Moscow seems determined to finish the operation on its town time table, and not one imposed by outsiders.
Jonah Hull, also reporting for Al Jazeera from Tbilisi, said Russia was sending "all sorts of mixed signals" and in the same breath saying that the pull out is underway.
He said Al Jazeera's correspondents had seen with their own eyes that Russia is "simply making no preparations to withdraw at all".
The United States has warned Russia to stop what it calls Moscow's "dangerous game" of using its military to assert its power.
Condoleezza Rice, the US secretary of state, is expected to push Nato allies to send a strong message to Russia that it must stick to its ceasefire commitment with Georgia or risk diplomatic fallout.
At Washington's request, the 26 foreign ministers of Nato member countries are meeting to reaffirm their solidarity with Georgia.
"Russia will pay a price," Rice said on Monday before flying to Brussels for the talks.
"We are going to send the message that we are not going to allow Russia to draw a new line at those states that are not yet integrated into the transatlantic structures like Georgia and Ukraine. We are determined to deny them their strategic objective."
Russia promised to start withdrawing forces on Monday back to positions in Georgia's breakaway South Ossetia province in line with a peace deal brokered last week by Nicolas Sarkozy, the French president.
And the deputy chief of staff of Russia's army said on Monday that the withdrawal had begun.
Russian forces are concentrated in the town Gori and were also roaming the western town of Senaki, where they have occupied a Georgian military base.
Witnesses also reported Russian patrols in the port city of Poti, which has been repeatedly raided and there were also Russian forces in and around the town of Zugdidi, near the border with Abkhazia.
Rice has accused Moscow of using "disproportionate force" against its neighbour, whose hopes of joining Nato have angered Russia.
The US secretary of state is scheduled to travel to Warsaw later on Tuesday where she is to sign a deal on installing a missile defence shield pact with Poland - a move certain to further increase tensions with Russia.
US diplomats denied Russian claims that Washington wants to break up the Nato-Russian Council which was set up in 2002 to improve relations between the former Cold War foes.
But a senior US official said on Monday that the alliance would have to rethink a range of planned activities - from a meeting with Russia's defence minister foreseen in October, to regular military consultations in areas such as counterterrorism, managing air space or rescue at sea.
|Rice is expected to push Nato to affirm its commitment to Georgia [AFP]
Some Nato officials said that approach was very likely to win support at Tuesday's emergency meeting, despite wariness among some European allies about further damaging relations with Moscow.
Despite one senior US official's assurance that "you'll see a Nato more united than you might expect", some diplomatic sources said the subject of Russia's role in Georgia had split Nato members.
Britain, Canada, the US and most Eastern European member states are in one camp seeking a tough stance on Russia's actions, the sources said.
But most of Western Europe, led by France and Germany and backed by Hungary and Slovenia among others, were more cautious of further hurting ties with Moscow.
Russia's ambassador to Nato warned that an "anti-Russian propaganda campaign" could jeopardise "the quality of co-operation" and that ties between Moscow and the alliance would suffer if the Nato foreign ministers failed to reach a "responsible decision".
"We hope that decisions by Nato will be balanced and that responsible forces in the West will give up the total cynicism that has been so evident [which] is pushing us back to the Cold War era,'' Dmitry Rogozin told reporters on Monday.
"We don't want to hear that [Mikheil] Saakashvili is a saint," he added, comparing the Georgian president's actions in the breakaway province of South Ossetia to the worst excesses of Hitler and Stalin.
The Nato meeting will also discuss support for a planned international monitoring mission in the region and a package of support to help Georgia rebuild infrastructure damaged in the conflict with Russia.
The ministers are also expected to restate Nato's firm opposition to the separatist ambitions of Georgia's pro-Russian breakaway regions South Ossetia and Abkhazia.
Saakashvili has accused Nato leaders of encouraging Russia's move into Georgian territory by postponing a decision in April to put Georgia and Ukraine on a fast track to Nato membership.
The alliance had held off because Germany and France were wary of Russian opposition to the move, since Russia is Europe's main energy supplier.
But on a visit on Sunday to Tbilisi, Angela Merkel, the German chancellor, repeated Western promises that Georgia will eventually join Nato.