By Chloe Arnold
BBC regional correspondent
Georgia's president has called for economic sanctions to be imposed on a renegade Black Sea region after its leader defied the central government.
Saakashvili wants to be able to travel through Ajaria
Moscow has warned Georgia's government not to interfere in the semi-autonomous Ajaria region.
Western governments, which are backing the construction of a multi-billion dollar pipeline in the region, are keeping a watchful eye on events.
What began as a local spat threatens to turn into an international incident.
The Georgian leader, Mikhail Saakashvili, called for an economic blockade on
Ajaria, after he was refused entry into the Black Sea territory.
Mr Saakashvili and the Ajarian leader Aslan Abashidze are arch rivals.
Mr Abashidze strongly opposed the western-leaning Georgian president who swept to power after staging peaceful protests to oust the previous leader, Eduard Shevardnadze.
Mr Abashidze maintains strong links with Moscow, and has appealed to Russia to help in the dispute.
Ajaria depends on income from transited goods across its territory
Its port ships around 200,000 barrels of oil a day
Ajaria has run its own affairs, withholding tax payments from central government in Tbilisi
There are fears Russia could deploy troops from its military base in Ajaria to combat Georgian forces which have been placed on high alert.
There is growing concern in the west about the deteriorating situation in Georgia.
Western investors have poured billions of dollars into the construction of a pipeline to transport Caspian Sea oil through the troubled region.
Any conflict there would put the security of the pipeline in jeopardy.
On Monday, Mr Saakashvili tried to ease tensions by ruling out the use of force against Ajaria, and returning to the capital Tbilisi.
But the standoff is expected to rumble on.