BuzzFeed has obtained a statement from Facebook in which the tech giant admits, for the first time, that some Russia-linked accounts may have used its platform to try to interfere in the UK’s European Union referendum vote in June 2016.

Which means Russian agents weren’t just using Facebook to meddle in the 2016 US presidential election, and in other recent elections in the West — such as those in France and Germany.

Elections are of course a huge deal but the result can at least be reversed at the ballot box in time. The in/out Brexit referendum in the UK was no such standard vote. And there is no standard process for reversing the result.

So if Kremlin agents also used Facebook to influence people in the UK to vote for Brexit that would be hugely significant — and further evidence that social media’s connective tissue can be used to drive and inflame societal divisions.

“To date, we have not observed that the known, coordinated clusters in Russia engaged in significant coordination of ad buys or political misinformation targeting the Brexit vote,” a Facebook spokesperson told BuzzFeed in a carefully worded statement.

Which begs the question how much Russian Facebook activity did target the Brexit vote? We asked Facebook how many socially divisive Russian-backed ads ran before Brexit. Facebook declined to comment.

While its claim not to have found “significant coordination” of Russian activity ahead of the Brexit vote might sound like ‘case closed’ on the EU referendum front, the company has consistently sought to play down the impact of Facebook-distributed Russian misinformation — with CEO Mark Zuckerberg initially describing it as a “pretty crazy idea” that fake news could have influenced voters in the US election.

Nearly half a year later, after conducting an internal investigation, Facebook conceded there had been a Russian disinformation campaign during the US election — but claimed the reach of the operation was “statistically very small” in comparison with overall political activity and engagement.

Then in September another tidbit came out when it said it now believed potential pro-Kremlin entities could have spent up to $150,000 on its platform to buy 3,000 ads to between 2015 and 2017. It said the ads were tied to 470 accounts — some linked to a known Russian troll farm called the Internet Research Agency.

It also agreed to share the Russian backed US political ads with congressional investigators looking into US election-related disinformation. Though it rejected calls to make all the ads public.

Finally, at the end of last month, about a year after its CEO’s denial of the potency of political disinformation on his mega platform, Facebook admitted Russian-backed content could have reached as many as 126 million people in the US.

It now estimates the number of pieces of divisive content at 80,000, after being asked by congressional investigators to report not just direct Russian-bought ads but organic posts, images, events and more, which can also of course become viral vehicles of disinformation on Facebook’s algorithmically driven platform.

So there’s a reason to be cautious about accepting at face value the company’s claim now that Russian Brexit meddling existed on its platform but was not significant.

Giving a speech yesterday, the UK prime minister set out in no uncertain tones her conviction that Russia has been using social media platforms to try to interfere with Western democracies, directly accusing Vladimir Putin of seeking to sow social division by “weaponizing information” and planting fake stories.

Multiple Twitter accounts previously linked to Russia’s Internet Research Agency have also been identified as engaging in Brexit-related tweeting, according to the Times — linking Russian-backed election meddling troll activity to the UK’s EU referendum vote too.

On Friday, Wired detailed some of the Russian-backed Twitter accounts and 2016 Brexit-related tweets — including tweets apparently seeking to conflate Islam with terrorism, and others aiming to stir up anti-immigrant sentiment such as by spreading racial slurs.

We asked Twitter how many accounts it has linked to pro-Kremlin entities that were also tweeting about Brexit ahead of the referendum vote. At the time of writing the company had not responded.

Meanwhile Russia continues to amuse itself with a spot of public Twitter trolling of the UK PM…

The Russian Foreign Ministry's official Twitter account is trolling our prime minister.

Can someone explain what this means? Hybrid warfare's over? We're now deep into postmodern warfare? pic.twitter.com/la97GLe7BL — Carole Cadwalladr (@carolecadwalla) November 14, 2017

A UK parliamentary committee which is investigating fake news has previously requested data from Twitter and Facebook on Russian accounts which posted about the EU referendum.

Commenting on the cache of Russian tweets now linked to Brexit, Damian Collins, the MP leading the inquiry, told Wired: “I think it shows that Russian-controlled accounts have been politically active in the UK as well as America. This could just be the tip of the iceberg because we’ve only really just started looking and doing a proper detailed study of what accounts linked to Russian organisations have been doing politically.”

The UK’s Brexit vote was both a shock result and a close one, with 51.9 per cent voting to leave the EU vs 48.1 per cent voting remain.

It caused huge immediate political upheaval — with the then UK Prime Minister resigning immediately. There was also major drop in the value of pound sterling. (The pound remains down around 11 per cent vs the dollar and 15 per cent vs the euro.)

While Brexit-based uncertainty continues to impact almost every aspect of day-to-day political activity in the UK, given the scale of the task facing ministers to try to unpick more than 40 years of EU agreements — clearly deflecting the government from being able to pursue a wider policy agenda as ministers’ fixed firefighting focus is on trying to enact Brexit without causing even greater disruption to UK businesses and citizens.

Scores of European ministers and civil servants are also having to expend further resources to manage Brexit vis-a-vis their own sets of priorities and to shape whatever comes after.

The incentive for Russia to have sought to run a disinformation campaign to encourage disunity in the European Union by encouraging a vote for Brexit is clear: Instability weakens your opponents.

Whether Putin’s agents were merely dabbling with Brexit disinformation as they geared up for a more major disinformation push focused on the US election remains to be seen. But given the closeness of the Brexit vote — and the long term disruption Brexit will undoubtedly cause — then any Russia-backed interference deserves to be quantified in full.

So we’re all looking at you, Facebook.