Russia is accused of having tried to influence the referendum in Moldova, which concerned writing the country's striving for EU membership into the constitution.
When almost all votes had been counted, the EU supporters had received 50.4 percent. This meant a minimal lead of 13,000 votes.
EU Commission President Ursula von der Leyen sent congratulations on Monday:
"Congratulations to the people of Moldova and to you (Sandu). You have done it again."
Through the referendum, Moldova has overcome a major obstacle on the path to becoming an EU member.
Russian influence
But for a long time, it looked like the no-side might unexpectedly win.
The President commented on the no-side's unexpectedly strong result on Sunday as a consequence of democracy and freedom in the country being "subjected to an attack of unprecedented scope".
Russian influence operations have been going on for several months, according to Sandu.
Even the EU Commission President claimed Russian involvement in a post on X:
"Moldova has shown its independence, its strength, and that the country wants a European future, despite Russia's hybrid tactics."
The Organization for Security and Co-operation in Europe (OSCE), which has election observers on site, said in an initial report that the election had been conducted correctly, despite "serious attempts to undermine the election's integrity".
Bought votes?
The suspicions concern an enormous influence campaign, where votes from hundreds of thousands of people may have been bought by pro-Russian groups. Last week, over 100 Moldovans were also arrested who were allegedly trained in Moscow to create disturbances around the voting.
Russia has denied involvement in the election and demands evidence for the accusations. Furthermore, the Kremlin's spokesperson, Dmitrij Peskov, claims, without presenting any evidence, that they have discovered "deviations" in the vote count.
Wants into the EU
EU-friendly Sandu was the driving force behind Moldova's decision to apply for EU membership in 2022, after Russia's full-scale invasion of Ukraine.
Simultaneously with the referendum, a presidential election was held, where Maia Sandu received the most support with 42 percent. However, since she did not receive over 50 percent, there will be a second round of voting on November 3, where she will face the pro-Russian candidate Aleksandr Stoianoglo, who received around 26 percent of the votes.