A close-cut majority of 50.17 per cent voted "yes" in Moldova's pivotal referendum on joining the European Union (EU), nearly final results showed on Monday, after President Maia Sandu said Sunday's twin votes had been marred by "unprecedented" outside interference.
The tight finish - with fewer than 1.5 per cent of the ballots still to be counted - is far from a resounding endorsement of the pro-EU path that Sandu has pursued over four years at the helm of the small ex-Soviet republic tugged between Russia and the West.
A presidential election, which took place simultaneously, handed Sandu 42 per cent of the vote while her main rival, former prosecutor-general Alexandr Stoianoglo won 26 per cent, setting up a tightly fought run-off between the two on November 3.
The votes, which took place after a slew of allegations of election meddling, were seen as a test of the southeast European nation's commitment to join the European Union and escape Moscow's orbit for good.
The tight referendum result puts Sandu in a weaker position going into the second round since she has championed EU integration.
The Kremlin on Monday said Moldova's election was not free and the results showed a "hard-to-explain" increase of votes in favour of President Maia Sandu and the European Union.
Moldova began the long process of formal accession talks in June and under Sandu has aimed to join by 2030. Ties with Moscow have deteriorated as Sandu condemned the Kremlin's invasion of Ukraine and diversified energy supply away from Russia.
Stoianoglo has said that if he comes to power, he would develop a "balanced" foreign policy involving ties with the EU, Russia, United States, and China. He boycotted Sunday's referendum, calling it a ruse to boost Sandu's haul at the election.
In the early hours of Monday, Sandu addressed Moldovan citizens, saying there was "clear evidence" that criminal groups working together with "foreign forces hostile to our national interests" had sought to buy off 300,000 votes.
She said this amounted to "fraud of unprecedented scale".
"Criminal groups... have attacked our country with tens of millions of euros, lies and propaganda, using the most disgraceful means to keep our citizens and our nation trapped in uncertainty and instability," she said.
While still waiting for the final results, she said, Moldova would "respond with firm decisions", without elaborating.
In the run-up to the vote, authorities made repeated statements alleging concerted attempts to meddle in the vote by fugitive tycoon Ilan Shor, who lives in Russia.
Russia, which accuses Sandu's government of "Russophobia", denied interfering, while Shor denies wrongdoing.