The yes campaign had 50.39% of votes with just a handful of ballots left to be counted, said the country's electoral commission.

It appeared to be behind until the last few thousand votes from Moldavans living abroad were tallied up.

Voters were asked whether to enshrine the goal of EU membership in the country's constitution.

Moldova's pro-EU president has accused groups "working together with foreign forces" of trying to buy 300,000 votes.

A European Union spokesman also claimed there had been "unprecedented intimidation and foreign interference by Russia and its proxies".

Moldovan police said money and documents allegedly linked to Russian-backed groups had been seized.

The Kremlin, which denies the claims, criticised the vote and said the "opposition was deprived of the opportunity of engaging in the electoral process".

It said the "election was not free" and the "sudden increase in votes" for the pro-EU side was "difficult to explain".

Moscow is not keen to give up influence in the former Soviet state, a country of about three million strategically positioned next to Ukraine and the Black Sea.

Moldovans also voted simultaneously in a presidential election.

President Maia Sandu collected more votes than rival Alexandr Stoianoglo - 42% to 26% - but was short of an overall majority.

It sets up a run-off next month between Ms Sandu and Mr Stoianoglo, a former prosecutor-general backed by the pro-Russian Party of Socialists.

Moldova, one of the poorest countries in Europe, applied to join the EU after Russia invaded Ukraine.

The long process of accession talks began in June and President Sandhu has said she hopes to become a member by 2030.