Georgian prosecutors on Wednesday launched a probe into the alleged "falsification" of the country's parliamentary election and summoned pro-Western President Salome Zurabishvili for questioning after she accused the ruling Georgian Dream party of fraud.
The announcement came after several EU countries criticised "irregularities" in the vote and called for an investigation. US President Joe Biden said he was "deeply alarmed" by democratic "backsliding" in the Caucasus country.
Tbilisi was plunged into political uncertainty after Saturday's election. The pro-Western opposition said the vote was "stolen" and refused to recognise its results.
Zurabishvili -- at loggerheads with the ruling party -- has declared the election results "illegitimate", alleging election interference by a "Russian special operation".
"The Prosecution Service of Georgia has launched an investigation into the alleged falsification of the parliamentary elections," prosecutors said in a statement.
It said Zurabishvili "is believed to possess evidence regarding possible falsification" and has been summoned to the investigative agency for an interview" on Thursday.
Opposition parties have said they would not enter the new "illegitimate" parliament and demanded "fresh" elections run by an "international election administration."
Tens of thousands rallied in Tbilisi on Monday to protest. The United States and European Union have condemned electoral "irregularities".
Tbilisi has been rocked by protests this year over several repressive laws passed by Georgian Dream, with opponents accusing the party of steering the Caucasus country towards the Kremlin.
Georgia's central election commission has said it is conducting a partial recount of ballots at some 14 percent of precincts.
Near-complete election results showed Georgian Dream party won 53.9 percent, compared with 37.7 percent for an opposition coalition.
Biden said Tuesday that the vote had been marred by "voter intimidation and coercion."
He called on Tbilisi to "begin an immediate, inclusive dialogue with all political forces in Georgia about restoring election integrity."
European Union council chief Charles Michel has said Georgia's authorities should "swiftly, transparently and independently investigate and adjudicate electoral irregularities".
A group of Georgia's leading election monitors said they had uncovered evidence of complex scheme of large-scale electoral fraud that has swayed results in favour of the ruling party.
In an interview to AFP on Monday, Zurabsivhili claimed that "quite sophisticated" fraudulent schemes were used in the vote.
She alleged that Georgian Dream's "electoral propaganda was totally copied from Russian propaganda" and "they have PR people... who come from Russia".
Georgian Dream's critics accuse the party of derailing efforts to join the EU and of bringing the ex-Soviet country back into the Kremlin's orbit.
Georgia's increasingly conservative leadership has rejected claims it is taking the country away from EU membership goals, whih is enshrined in the constitution.
Prime Minister Irakli Kobakhidze insisted that joining the EU was his government's "top priority" and that he expected a "reset" with the bloc in coming months.
Kobakhidze met with Hungarian Prime Minister Viktor Orban -- the EU rebel who has retained ties with Moscow despite its Ukraine invasion -- on Tuesday. Orban travelled to Tbilisi in a show of support for Georgian Dream.
Brussels put Tbilisi's accession process on halt after Georgian Dream passed a law this year on "foreign influence" that opponents say mirrors Russian legislation.
Tbilisi passed the law despite massive demonstrations. The US imposed sanctions on Georgian officials following the protests.
