Last spring, customs officers in the tiny nation of Moldova struck gold. Acting on a national intelligence tip-off from, they intercepted more than 100 passengers arriving from Russia via Armenia, each carrying bundles of cash just shy of €10,000 – the threshold for mandatory declaration. In a single night authorities at Chișinău airport seized more than €900,000.

Moldovan officials swiftly announced that the cash couriers were part of a scheme allegedly led by a Kremlin-linked fugitive oligarch and aimed at financing protesters and buying votes in this month’s presidential election and pivotal EU referendum.

The operation offered an early indication of what Moldovan and western officials have described in interviews with the Observer as an unprecedented effort by Russia to undermine the country’s bid for EU membership and weaken the authority of its pro-western president through a series of destabilising campaigns.

“Russia is pouring millions in dirty money to hijack our democratic processes. This isn’t just meddling – it’s full-blown interference aimed at destabilising our future. And it is alarming,” said Olga Roşca, a foreign policy adviser to the pro-western president, Maia Sandu.

The election, set for 20 October, in which Sandu faces re-election, is to be held on the same day as a referendum asking Moldovans whether they support constitutional changes that could eventually enable the country – one of the poorest in Europe – to join the EU.

Roşca said the government estimated that at least €100m was being funneled into Moldova from Russia to manipulate the elections and EU referendum. It is not the first warning about Russian interference: in June, the US, UK and Canada said Moscow was trying to meddle in Moldovan politics and would seek to provoke mass protests if its campaign fails.

Since the breakup of the Soviet Union, Moldova has gravitated between pro-western and pro-Russian courses, though the shadow of the Kremlin has always loomed large. Moscow also has 1,500 troops stationed in Transnistria, a region run by pro-Russian separatists who broke away from the control of Moldova’s government in a brief war in the 1990s.

Sandu, a former World Bank official, was elected president in November 2020, riding a wave of popularity as an anti-corruption reformer with a pro-European agenda. She has advocated a humble lifestyle – a sharp contrast to the bombastic, predominantly male politicians who have long dominated Moldovan politics.

In a recent interview, the president said she was sharing a two-bedroom apartment with her mother, while in her asset declaration from 2023 her bank balance was recorded as $600.

In 2021, Sandu’s pro-western party, PAS, won a majority in the country’s parliamentary elections, giving her unprecedented power to implement reforms and push the country toward the west. But, three years later, Moldova remains mired in economic and political instability.

First, the country was plunged into an energy crisis when Kremlin-controlled Gazprom slashed gas supplies to the country by one-third and demanded more than double the previous rates to maintain the flow, in what was widely seen as political payback from Moscow for Sandu’s pro-western stance. Then, Russia’s war on Ukraine pushed Moldova into a broader financial crisis.

Located just a few hours drive from Odesa, Moldova took in the highest number of Ukrainian refugees per capita, placing immense strain on its healthcare system, public services, and infrastructure. Inflation surged by as much as 40% as trade with both Moscow and Kyiv sharply declined.

Stray Russian missiles from the conflict added to the growing sense of danger, while the Russian troops stationed in Transnistria further amplified anxieties.

“Sandu promised a lot, but the geopolitical situation has been very tough on her. They have not been able to deliver on all promises,” said a western official in Moldova, reflecting on the growing frustration among some Moldovans with Sandu and her party.

“There is growing apathy and disappointment, which provides a fertile ground for Russia,” the official added.

Sandu remains the favourite to win the first-round presidential vote against 10 challengers, but she is facing a tricky second-round runoff.

She is also leading the “Yes” campaign for the EU referendum, with polls showing 55-65% of voters in favour of joining the bloc. In a major boost for Sandu, Moldova officially began EU accession negotiations in June. However, scepticism remains high about the country’s ability to implement the necessary democratic and judicial reforms in the near future.

Critics from the opposition have accused Sandu of politicising the referendum by holding it on the same day as the presidential election, suggesting that the move is designed to boost her own political chances. “The referendum is a very cynical move,” said Alexandr Stoianoglo in Chișinău, one of Sandu’s main rivals from the Russian-friendly socialist party, who is polling at 12%.

“EU integration should not be used for personal gain,” he added.

But those close to Sandu said Russia’s growing influence means the country cannot afford to wait. “We have a unique opportunity: Moldova has a pro-European president, parliament, and government. The EU is open to our membership, with all countries backing accession talks last June,” said Roşca. “Moldova’s survival as a democracy is on the line, and the geopolitical stakes are higher than ever,” said Roşca.

The biggest threat for Sandu comes from abroad, say her supporters. In particular, the fugitive pro-Russian businessman Ilan Shor, a vocal – and wealthy – opponent of EU membership who has been sanctioned by the west.

Shor was sentenced to 15 years in prison last year in absentia in connection with his role in the disappearance of $1bn from Moldova’s banking system. He fled to Israel and then Moscow where he set up a political movement aimed at destabilising the current government in Chișinău.

At a press conference last Thursday, national police chief Viorel Cernăuțanu accused Shor and Moscow of establishing a complex “mafia-style” voter-buying scheme and bribing 130,000 Moldovans to vote against the referendum and in favour of Russia-friendly candidates in what he called an “unprecedented, direct attack”.

Officials in Chișinău also believe Shor is behind a wave of pre-election vandalism attacks on government buildings, accusing him of recruiting young people who were allegedly trained in Moscow to cause unrest in the country. “We are prepared for anything in the coming weeks,” said a security official in the city. “It will be a variety of misinformation campaign, violent street protests and crude vote buying,” they added.

Shor did not reply to questions from the Observer. But he has done little to distance himself from the accusations of trying to interfere in Moldovan politics from abroad. Through the social network Telegram, he has offered to pay voters the equivalent of $29 if they registered for his campaign, promising money to people who would “convince as many people as possible at their polling station” to vote “no or abstain” in the referendum.

He has publicly pledged to pay Moldovans for publishing anti-EU posts on Facebook and Telegram.

The central “fear-mongering” narrative that Shor has been promoting centres around the claim that Chișinău’s pro-European policies are pushing the country towards war with Russia, said Vadim Pistrinciuc, the director at the Institute for Strategic Initiatives of Moldova, a thinktank.

“We have never faced this level of foreign interference,” he added.

Worryingly for officials in Chisinau, Shor’s tactics have proven effective elsewhere the country.

Last year, Yevgenia Gutsul, a previously unknown Shor-backed candidate, caused a political earthquake by winning the elections of governor in Gagauzia, another small, Russian-speaking semi-autonomous region in the south of the country.

Pro-Russian sentiments have always been high in Gagauzia, a region populated by a Turkic ethnic minority, which has had an uneasy relationship with the capital Chisinau since the 1991 breakup of the Soviet Union.

But Gutsul’s rise from obscurity and her ties to the Kremlin has stunned even seasoned observers and have prompted questions over Moscow’s role in her elections.

“She was polling at zero two weeks before the elections and then suddenly she appears and wins,” said Mihail Sirkeli, founder of Nokta, an independent media outlet based in Gagauzia.

Gutsul, who has openly declared running “a pro-Russian party” and travelled to Moscow to meet with Vladimir Putin after her election, is currently under investigation for allegedly funnelling Russian funds to a party associated with Shor.

“Shor is looking to repeat the Gagauzia playbook across the country,” said a western diplomat in Chisinau.

For now, officials in Moldova believe Moscow is concentrating its efforts on influencing the EU referendum, rather than the presidential elections where Sandu remains by far the most popular politician.

“If the referendum passes, it will lead to constitutional changes, which are harder to reverse in the long term compared to election outcomes,” said a senior Moldovan official.

But even if Sandu survives this month’s vote and referendum, her team expects renewed Kremlin efforts next year when her party faces re-election in the country’s parliamentary elections.

“Russia’s goal is clear: to keep Moldova stuck in a grey zone,” said Roşca. “If they lose Moldova, they lose a strategic foothold in the region.”