Georgians to vote in watershed elections widely seen as decisive for the fate of the country's relationship with the European Union.

The parliamentary elections pit the ruling party against pro-Western opposition forces.

Brussels has warned that the vote will determine European Union candidate Tbilisi's chances of joining the bloc.

"Georgia's traditionally fractured opposition forces have managed to forge an unprecedented united front against the Georgian Dream," said analyst Gela Vasadze at Georgia's Strategic Analysis Centre.

The potential coalition grouping includes Georgia's main opposition force, jailed ex-president Mikheil Saakashvili's United National Movement (UNM) and Akhali, a recently formed party headed by former UNM leaders.

Undecided voters

Along with several smaller parties, they have signed up to a pro-European policy platform outlining far-reaching electoral, judicial and law enforcement reforms.

But the outcome of the vote is far from a foregone conclusion, as more than a quarter of respondents told the pollster they were either undecided or refused to name their preferred political force.

Voting will begin at 0400 GMT and end at 1600 GMT, with exit polls set to be released on closing.

The elections, held under a proportional party list system, will be monitored by international observers from the Organisation for Security and Cooperation in Europe.