Georgia's prime minister has hailed a "landslide" election result, rejecting allegations of vote-rigging and violence.

"Irregularities happen everywhere, in every country," Irakli Kobakhidze of the Georgian Dream party told the BBC's Steve Rosenberg in an exclusive interview.

Official preliminary results from Georgia's election commission gave the ruling Georgian Dream an outright majority of 54%, despite exit polls for opposition TV channels suggesting four opposition parties had won.

Georgia's pro-Western president, Salome Zourabichvili, has condemned the "total falsification" of the vote and called for opposition supporters to rally outside parliament on Monday.

Election observers in this South Caucasus state bordering Russia have complained of an "uneven playing field" in the election, suggesting the scale of vote violations may have affected the result.

The US and European Union have backed the monitors' calls for an independent investigation. US Secretary of State Antony Blinken urged Georgia's leaders to "respect the rule of law, repeal legislation that undermines fundamental freedoms, and address deficiencies in the electoral process together".

However, the prime minister insisted that out of 3,111 polling stations, there had been incidents in "just a couple of precincts" but that in all the others "the environment was completely peaceful".

Georgian Dream, known as GD, has become increasingly authoritarian, recently passing Russian-style laws targeting media and non-government groups who receive foreign funding, and the LGBT community.

The European Union has responded by freezing Georgia's bid to join the EU, accusing it of "democratic backsliding". Tbilisi was awarded candidate status only last December and an estimated 80% of Georgians want to be part of the 27-country union.

Even before the results came out, one EU leader, Hungary's Viktor Orban, congratulated Georgian Dream on securing a fourth term and is due to travel to Georgia on Monday.

The ruling party says it is keen to kickstart talks on reviving its EU bid, but the sight of Orban arriving in Tbilisi two days after a contested election is unlikely to go down well in Brussels. Orban is seen as Russia's closest ally in the EU, and the European Parliament has denounced his government as a "hybrid regime of electoral autocracy".

GD sees itself as closely aligned to Orban's style of social conservatism. The party's EU integration committee head, Maka Bochorishvili, has told the BBC: "Being conservative is not forbidden, family values are part of European values as well."

Responding to widespread reports of vote fraud in the election, the head of the member states' European Council, Charles Michel, said "alleged irregularities must be seriously clarified and addressed".

"Of course we have to address these irregularities happening on the day of the election or before," the Georgian prime minister told the BBC. "But the general content of the elections was in line with legal principles and the principle of democratic elections."

The four opposition groups have refused to recognise the election result, condemning it as falsified, and they have accused the ruling Georgian Dream party of stealing the vote.

Surrounded by leaders of the opposition, Salome Zourabichvili said the vote could not be recognised and called on the people to gather in Rustaveli Street, the big avenue that runs past parliament, to "defend our constitutional right".

She also accused Russia of interfering in the vote without giving details, although Nika Gvaramia of opposition alliance Coalition for Change has made allegations of an "openly planned special operation by Russian intelligence services".

Coalition for Change and another opposition group, United National Movement, have said they will boycott parliament.

The opposition will now hold 61 seats in the 150-seat parliament, while Georgian Dream will have 89 - a majority but not big enough to enact the kind of constitutional change it wanted, to carry out its threat to ban opposition parties.

Two exit polls carried by Western pollsters for opposition TV channels suggested that the opposition had won, and that GD had secured a maximum of 42%, not 54%.

In his BBC interview, Kobakhidze accused the opposition of lying, arguing that they had also said the vote had been falsified in 2016, 2020 and 2021.

"Of course they have now no other way, so they have to tell their supporters that either they were lying or the government rigged the elections."

An electronic vote-counting system was used for the first time on Saturday, and the prime minister said that made the election impossible to rig: "There is zero space for manipulation."

The chairman of Georgia's election commission who oversaw the new system hailed the vote as largely peaceful and free, but a very different picture has emerged from monitoring groups that have presented their initial findings.

Georgia's Isfed group reported a litany of violations, including bribery, intimidation and ballot-stuffing, and said the result "cannot be seen as truly reflecting the preferences of Georgian voters".

Per Eklund, a former EU ambassador who was part of the National Democratic Institute delegation, said it was clear the pre-election period in particular had failed to meet democratic standards.

"Voter intimidation... up to and on election day severely undermined the process," he said.

Georgian Dream's billionaire founder, Bidzina Ivanishvili, has in recent months stoked up anti-Western rhetoric, accusing an unidentified "global war party" of aiming to drag his country into the war in Ukraine.

His unfounded claims have led to fears that his party is adopting Russian-style laws and returning to Russia's sphere of influence, 16 years after a five-day war in which Russian troops invaded Georgia.

Russian commentators have widely welcomed Georgian Dream's victory as an indication that Georgia will begin to pivot back to Moscow.

And Russian foreign ministry spokeswoman, Maria Zakharova, criticised the Georgian president's comments rejecting the election result and casting doubt on Georgia's joining of the EU.

"To think the EU can still offer anyone a 'European future' is simply stupid," she said on social media.

In his BBC interview, Irakli Kobakhidze denied the opposition's accusation that the government was pro-Russian and "pro-Putinist". He said they had been trying to damage the government's reputation with Georgia's 3.7 million population.

The prime minister said that Georgia was the only country in its region with no diplomatic relations with Russia, because of Russia's occupation of 20% of Georgian territory since the 2008 war.