Russia closed the Upper Lars checkpoint in 2006 in a move Georgian officials said was politically motivated amid tensions over Tbilisi's efforts to build closer ties with the West, particularly Nato.
War of 2008
Tensions between the two sides reached a flashpoint in August 2008, when Russian forces poured into Georgia to repel a Georgian military attempt to retake South Ossetia, which had received extensive backing from Moscow for years.
Russia later mostly withdrew to within South Ossetia and Abkhazia, which Moscow recognised as independent states in August last year.
The Kremlin's decision was condemned by the most nations and only Nicaragua, Venezuela and the Pacific island state of Nauru have recognised the two territories.
The other two roads linking Georgia and Russia run through South Ossetia and Abkhazia, effectively barring them to international traffic.
The closing of the Upper Lars crossing also dealt a heavy blow to neighbouring Armenia, which relied on the crossing as its only overland route to Russia, the country's key economic partner.
Dmitry Medvedev, Russia's president, hinted at a thaw in relations with Georgia earlier this month, saying he saw "no obstacles" to opening the Upper Lars crossing and resuming direct flights between Russia and Georgia.
Russia cut air links with Georgia during the war, only four months after they had resumed following an 18-month embargo.
Georgian Airways, the country's privately owned flagship airline, this week asked Russia to lift the embargo but has yet to receive a reply.
The company said it had requested the resumption of charter flights between Moscow and Tbilisi for the holiday period of December 26 to January 15 and the resumption of regular flights starting from January 5.