Georgians were voting Saturday in closely watched municipal elections, a day after ex-president Mikheil Saakashvili's arrest on his return from exile deepened a protracted political crisis in the Caucasus nation.
The detention of Georgia's foremost opposition figure raised the stakes in the elections seen as a key test for the increasingly unpopular ruling party.
Saakashvili founded Georgia's main opposition party, the United National Movement (UNM), and was president between 2003-2013.
The 53-year-old said Friday he had returned from Ukraine, where he heads a Ukrainian government agency steering reforms.
The flamboyant pro-Western reformer was detained shortly afterwards over a 2018 conviction in absentia on abuse of office charges. He denies wrongdoing and had denounced his sentence of six years in jail as politically motivated.
His jailing will almost certainly spark upheaval in the small ex-Soviet nation that has been plagued for years by political instability.
"I want to ask you all to go to the elections so that not a single vote is lost," he wrote on Twitter Saturday, posting a picture of a letter to supporters from prison.
"My freedom and, more importantly, the freedom of Georgia depends entirely on your actions and fighting ability."
Prior to his arrest, he posted a video message on Facebook calling on supporters to take to the streets against the government.
- Protracted crisis -
The municipal elections are being watched inside and outside Georgia for signs of the ruling party Georgian Dream backsliding on democracy.
Saakashvili -- who commands a fiercely loyal following -- called in one video Friday for his supporters to gather on the main thoroughfare in the capital Tbilisi on Sunday.
Critics have accused Georgian Dream -- in power since 2012 -- of using criminal prosecutions to punish political opponents and journalists. Interpol turned down requests from Tbilisi to issue a red notice against Saakashvili.
Opposition parties decried widespread fraud and refused to take their seats after parliamentary elections in October last year, which Georgian Dream won narrowly.
The EU mediated an agreement in May, under which Georgian Dream pledged to hold a snap parliamentary vote if it wins less than 43 percent in Saturday's local elections.
Georgian Dream, which was founded by the country's richest man and a former prime minister, withdrew from the agreement in July, but Saakashvili insists it remains in place.
Georgia's Western partners urged the EU-aspirant country's government to implement the agreement that envisaged sweeping political and judiciary reforms.
With concerns mounting in the West over the ruling party's democratic credentials, the United States has hinted at possible sanctions against Georgian Dream officials.