The Georgian opposition on Sunday called for protests and the European Union demanded an investigation into "irregularities" after a disputed legislative vote that showed a win for the ruling party.

Pro-Western President Salome Zurabishvili accused Moscow of being behind the alleged election fraud, calling it a "Russian special operation".

Amid angry opposition claims over the result, Zurabishvili called for a rally on Monday. Jailed former president Mikheil Saakashvili also called for mass protests.

The European Union had warned that Saturday's vote could determine Tbilisi's chances of joining the bloc.

EU council president Charles Michel wrote on X that Georgian authorities should "swiftly, transparently and independently investigate and adjudicate electoral irregularities and allegations thereof.

"These alleged irregularities must be seriously clarified and addressed," he said.

After meeting with opposition leaders in Tbilisi, Zurabishvili said there had been a "total falsification of the election".

"We are witnesses and victims of a Russian special operation, a modern form of hybrid war against the Georgian people," she said.

International observers said Saturday's election was "marred by an uneven playing field, pressure and tension". An EU parliament mission also expressed concern about "democratic backsliding", saying it had seen instances of "ballot box stuffing" and the "physical assault" of observers.

Saakashvili said on Facebook that opposition lawmakers should renounce their parliamentary seats.

"Now is the time for mass protests. We must show the world that we are fighting for freedom and that we are a people who will not tolerate injustice," he said.

Official tallies from more than 99 percent of precincts showed the ruling Georgian Dream party winning 54 percent of the vote, with the main pro-Western opposition coalition on 37.5 percent.

The result gives Georgian Dream 91 seats in the 150-member parliament – enough to govern but short of the supermajority it had sought to pass a constitutional ban on all main opposition parties.

"Our victory is impressive," Prime Minister Irakli Kobakhidze said in a statement, accusing the opposition of "undermining the country's constitutional order" by questioning his party's victory. (AFP)