Saakashvili has vowed to re-unite Georgia

The region - backed by Russia - broke away in a civil war after the Soviet Union collapsed in the early 1990s.

Mr Saakashvili questioned the 1992 deal that set up a peacekeeping force from South Ossetia, Georgia and Russia.

In response, South Ossetia's leader Eduard Kokoity said Mr Saakashvili comments "could lead to a new war".

In recent days, Georgia and South Ossetia appeared to be moving closer to war, with a string of clashes in the mountainous territory.

Georgia has also accused Russian peacekeepers of siding with the rebels and trying to arm them, while Moscow says Georgia is trying to trigger a military confrontation in South Ossetia.

However, earlier this month the three sides agreed in Moscow not to use force to try to end their simmering territorial conflict.

Saakashvili's pledge

Mr Saakashvili criticised the peace agreement, signed by his predecessor Eduard Shevardnadze, banning the Georgian flag from areas patrolled by peacekeepers.

SOUTH OSSETIA Profile: South Ossetia

"I heard recently, and one of the Russian peacekeepers confirmed this, that in the centre of Kartli [in South Ossetia] raising the Georgian flag is considered illegal," Mr Saakashvili - who has pledged to reunite his fractured country - said.

"If the previous Georgian authorities, representatives of Shevardnadze's regime, signed such agreements then we intend to withdraw from them and denounce these documents," the president added.

His remarks were immediately rebuked by Mr Kokoity.

"It is thanks to this very agreement that conflict was halted in 1992," South Ossetia's leader told Russia's Itar-Tass news agency.

Georgia wants South Ossetia and Abkhazia, another breakaway region, back under its control.

But South Ossetia - which claimed independence from Georgia - wants to join North Ossetia, which is ethnically similar and part of Russia.

Moscow does not formally recognise the South Ossetian government but has close contacts with the leadership. Most residents in the region have Russian passports and the Russian currency, the rouble, is widely used.