Saakashvili earlier signed the pact, brokered by Nicholas Sarkozy, the French president, on behalf of the European Union, following five hours of talks with Rice.
Saakashvili 'under pressure'
Neave Barker, Al Jazeera's correspondent in Moscow, said: "Essentially, in signing that document, Saakashvili has signed away Georgian influence in that part of the world so, of course, it's being hailed here in Moscow as a milestone.
"This essentially means that Georgia will no longer be able to station any peacekeeping forces within South Ossetia and Abkhazia.
"These will be replaced by Russian peacekeepers of the CIS group, plus international peacekeepers as well.
"Moscow is very happy that Saakashvili has agreed to sign ... no doubt under pressure by Condoleezza Rice.
He said Saakashvili's agreement to the deal was "a clear indication that Russia has managed to push through the six-point plan, plus its amendments, that was made here under the auspices of president Sarkozy in France."
'Bullying and intimidation'
Hundreds of Russian soldiers and more than a dozen armoured personnel carriers are reported to have reached a village 40km away from Tbilisi - the furthest push by Moscow into the country since Georgia launched its attack on the breakaway region of South Ossetia on 7 August.
Saakashvili said Russian tanks had also reached two other towns - Khashari and Borjomi - in central Georgia, which has not been independently confirmed.
|Russian forces are reportedly within 40km of the Georgian capital [AFP]
George Bush, the US president, has denounced Russian's military action in Georgia as being "completely unacceptable to the free nations of the world" and accused Moscow of "bullying and intimidation".
Saakashvili said in a joint news conference with Rice in Tibilisi: "We will never, ever surrender, give up our freedom and territory, we will definitely get rid of these invaders for good. I am totally convinced of that."
He also criticised the West for not granting Georgia Nato membership earlier this year, saying Russia had stepped up its military presence in the region following the decision.
He later told Al Jazeera that in not coming to Georgia's aid "the West made a great miscalculation ... people underestimated the threat".
Jonah Hull, Al Jazeera's correspondent in Tbilisi, said: "Saakashvili's public statements are aimed at domestic consumption ... they are for the Georgia public to listen to and, in terms of rhetoric, the Russians are doing the same.
He said the ceasefire agreement "would establish a ceasefire, withdrawal of forces and put international monitors on the ground".
But he added: "Resolving a territorial dispute over South Ossetia and Abkhazia will be much harder."
Angela Merkel, the German chancellor, had earlier secured the agreement of Dmitry Medvedev, the Russian president, to the EU-brokered deal but was told Moscow would guarantee the will of the people in the pro-Russian separatist regions.
Russian troops were reported on Friday to be stationed in Gori, Georgia's second city, the Black Sea port of Poti, and the western town of Zugdidi, which lies near another breakaway region, Abkhazia.
Meanwhile, Viktor Yushchenko, Ukraine's president, has said he had requested urgent talks with Moscow on the Russian navy's use of Sevastopol, a Ukrainian port, as the base for its Black Sea fleet.
Ukraine had said on Thursday it would make Russia seek official permission for movements of its warships based in the former Soviet state despite Moscow's objections.
Marc Garlasco, from the New York-based Human Rights Watch organisation, told Al Jazeera that both Russia and Georgia were using indiscriminate weapons in the conflict, including cluster bombs.
|Rice has called on Russia to start withdrawing from Georgia [Reuters]
Speaking in Tbilisi, Garlasco said: "We've been very concerned that both sides have not been following the Geneva Conventions, and supporting international humanitarian law here.
"It's quite shocking that in the year that 107 countries have agreed to ban cluster bombs, that the Russians are using them in this conflict now.
"Clearly we need to have some international body come here and do some credible investigation.
"Just to look at statements of casualties – the Russians are claiming 2,000 dead in South Ossetia - our investigation has shown 44 at this point. So we really need to have someone discern what the truth is."
Russian troops entered Georgia following Tbsili's August 7 offensive to retake South Ossetia, which achieved de facto independence from Georgia in the 1990s during the breakup of the Soviet Union.
Moscow, which firmly backs South Ossetia and Abkhazia, has issued Russian passports to most people in the two territories.