Georgia accused arch-rival Russia on Wednesday of deploying sophisticated S-300 missile defence systems in a second breakaway Georgian region, South Ossetia, as well as Abkhazia.

Moscow, which earlier this month announced it had placed S-300s in Georgia's rebel Abkhazia region, denied that the surface-to-air missiles had also been deployed in South Ossetia.

"Although Russia is not saying this, be sure that S-300s have already been deployed in the Tskhinvali region," Foreign Minister Grigol Vashadze told Imedi television, using the official Georgian name for South Ossetia.

Vashadze said that with the missiles in Abkhazia, South Ossetia and a Russian military base in neighbouring Armenia, "Russia has set up a triangle in the South Caucasus and regions adjacent to it which it will need for a confrontation with NATO or Turkey."

A defence ministry source in Moscow denied the deployment, telling Russia's Interfax news agency: "There are no S-300 systems in South Ossetia."

Russia's air force Commander-in-Chief General Alexander Zelin revealed earlier this month that S-300 missiles, one of the world's most powerful anti-aircraft weapon systems, had been deployed in Abkhazia.

The Kremlin later downplayed the announcement, saying the missiles had been deployed two years ago during its brief war with Georgia over the Moscow-backed rebel regions.

Tbilisi has denounced the deployment as an "extremely dangerous provocative step" and warned the systems pose a threat not only to Georgia but also to NATO countries.

Tbilisi and most of the international community insist that Abkhazia and South Ossetia are an integral part of Georgian territory, but Russia recognised the two regions as independent after the war.

First manufactured by the Soviet Union in 1978, the S-300 is a surface-to-air missile system capable of tracking and destroying ballistic missiles, cruise missiles, and low-flying aircraft at a range of up to 100-200 kilometres (62-124 miles).