At Sandu’s election headquarters on Sunday evening, the mood was extremely subdued, with one of her advisers describing the result so far as “not what we expected”.

Sandu, who has cultivated close ties with Moldova’s EU neighbours, had campaigned for the Yes vote in the referendum. She had previously said the vote was would set up the future of Moldova for “many decades ahead”.

When the first results began trickling in showing that the No vote had done better than expected, Sandu’s team put the disappointing results down to the first count coming in from villages and rural areas.

The big city count narrowed the lead for the No vote, but by 01:00 (22:00 GMT) few thought the Yes camp could still stand a chance.

Many of Sandu’s supporters left her headquarters in Chisinau where they had been hoping to celebrate her victory before the count was even over. The little EU flags they’d been given to wave have been abandoned, on chairs or strewn on the ground.

An adviser to Sandu suggested that “it looked like whatever they had planned, might have worked,” referring to allegations of vote-buying, linked to Russia.

Voter turnout stood at more than 51% when polls closed at 21:00 local time (18:00 GMT), making the referendum valid.

As the night went on, the gap narrowed even further.

Several presidential candidates boycotted the referendum. Aleksandr Stoianoglo said he did not support the idea of changing the constitution – although he added he was a supporter of his country’s “European aspirations”.

However, many young people queuing at polling stations on Sunday were vocal about their support for Moldova’s future as an EU member state, with some saying they were voting because they wanted to choose a European future for their country – for the sake of the economy and for more opportunities.

Some said they were fed up of being “pulled” towards Moscow, decades after the Soviet Union collapsed and Moldova became independent.