On Jan. 1, Bulgaria became the eurozone’s 21st member when it gave up its 145-year-old currency, the lev, for the euro. In Sofia and Brussels, this development was roundly celebrated as another step in the European Union’s economic and political integration.
What went largely unnoticed, however, is the extent to which Bulgaria’s adoption of the euro represents a strategic blow for the Kremlin. After years of sustained effort to block Sofia from joining the eurozone, Moscow failed to prevent a decision that anchors Bulgaria more deeply and irreversibly within the European project. The currency switch not only exposed the limits of Russia’s hybrid tactics but also narrowed its remaining leverage in the country.
On Jan. 1, Bulgaria became the eurozone’s 21st member when it gave up its 145-year-old currency, the lev, for the euro. In Sofia and Brussels, this development was roundly celebrated as another step in the European Union’s economic and political integration.
What went largely unnoticed, however, is the extent to which Bulgaria’s adoption of the euro represents a strategic blow for the Kremlin. After years of sustained effort to block Sofia from joining the eurozone, Moscow failed to prevent a decision that anchors Bulgaria more deeply and irreversibly within the European project. The currency switch not only exposed the limits of Russia’s hybrid tactics but also narrowed its remaining leverage in the country.
Russia has never fully accepted Bulgaria’s strategic realignment. Instead, it has continued to treat Bulgaria as contested ground, drawing on historical, cultural, religious, and economic ties—including energy dependence—in order to keep the country within what Russia perceives as its sphere of influence. Part of the Kremlin’s influence extends through the Bulgarian Orthodox Church, which maintains close ties with the Russian Orthodox Church; Moscow has long used the latter as a soft-power instrument to promote notions of Slavic and Orthodox brotherhood. For much of its modern history, Bulgaria was Russia’s most stalwart European ally, which left Moscow to exert its lingering influence even after Sofia’s entry into Western institutions, including NATO and the European Union.
From the Kremlin’s perspective, eurozone enlargement is not a neutral economic process. Seen from Moscow, any deepening of EU integration constrains its ability to exploit bilateral dependencies, apply selective pressure, create divisions within the bloc, and cultivate gray zones of influence on the EU’s eastern flank. Countries that adopt the euro become more closely tied to one another economically, financially, and politically, reducing opportunities for outside manipulation. While Bulgaria will remain vulnerable—after all, Slovakia’s use of the euro hasn’t prevented its government from aligning with the Kremlin when EU members vote on issues affecting Russia—eurozone membership limits the avenues through which Moscow has historically sought to influence Euro-Atlantic institutions.
Analysts had good reason to doubt that Sofia would complete the final two steps of EU integration, namely joining the Schengen area of borderless travel and the eurozone. Although Bulgaria has been an EU member since 2007, it continued to struggle with high inflation and corruption. While Bulgaria and Croatia entered the European Exchange Rate Mechanism—the mandatory two-year transition period before euro adoption—at the same time in July 2020, their trajectories soon diverged. Croatia advanced largely on schedule and adopted the euro in 2023. Bulgaria, by contrast, repeatedly postponed its target date—first to 2024 and then to 2025, before ultimately joining in 2026.
These delays were not merely technical, such as inflation exceeding the EU-mandated threshold. They were also driven by a surge in political and public qualms about deeper EU integration—an upswell of resistance that was actively fueled by Russian-linked influence operations and Bulgarian proxy actors aiding the Kremlin. Thus, Bulgaria’s stalled path to adopting the euro became a visible indicator of Russia’s ability to impede, though not ultimately prevent, EU integration.
In the lead-up to euro adoption, Moscow relied on a familiar toolkit of interference.
First, Russian-linked actors conducted extensive disinformation campaigns aimed at shaping public opinion against the euro. Russia used covert financial networks to spend tens of millions of euros on propaganda and interference in Bulgaria. Social media accounts linked to Russia or its Bulgarian proxies, as well as sympathetic traditional media outlets, amplified alarmist and often demonstrably false claims. These claims included the idea that euro adoption would trigger runaway inflation, lead to the confiscation of citizens’ savings, strip Bulgaria of its national identity, and subject the country to the dictates of Brussels. These narratives helped deepen societal division over euro adoption and reduce public support. A Eurobarometer poll conducted in late 2025 showed a plurality of 49 percent of Bulgarians opposed to the common currency, with only 42 percent in favor.
Second, openly pro-Russian forces in Bulgaria, most notably the far-right nationalist Revival party, echoed and legitimized these narratives. Revival, which has an official cooperation agreement with Russian President Vladimir Putin’s United Russia party, became the most visible domestic opponent of euro adoption. The party organized anti-euro rallies and protests, some of which featured Russian flags. Last February, party members stormed the EU mission in Sofia, throwing firecrackers, red paint, and Molotov cocktails at the building and setting its entrance door on fire. Revival party leaders repeatedly warned of an economic collapse similar to that experienced by Greece during the euro debt crisis, despite postcrisis eurozone reforms and Bulgaria’s markedly different fiscal position. Revival also pushed for a national referendum on euro adoption, a move rejected by parliament as incompatible with Bulgaria’s treaty commitments to the EU. Revival parliamentarians spread conspiracy theories, including claims that Brussels was planning to seize Bulgarians’ savings and that the confiscated funds would be used for military projects.
Third, these efforts fed into a broader strategy of institutional erosion. By casting doubt on the motives and competence of European institutions and Bulgaria’s own governing elites, Russian-linked campaigns sought to deepen cynicism, polarize society, and weaken trust in the democratic process. Bulgaria’s chronic political instability, characterized by short-lived governments, fragmented coalitions, and seven snap parliamentary elections in four years, made the country particularly vulnerable to Russian interference. Persistent governance crises created fertile ground for Euroskeptic messaging and for claims that integration with the EU was being imposed without popular consent.
Despite this strong and sustained pressure, Bulgaria’s pro-European parliamentary majority ultimately delivered. Successive governments that included the strongly pro-EU, anti-corruption coalition We Continue the Change-Democratic Bulgaria completed the necessary legal and technical steps required for adopting the euro. Key institutions withstood attempts to politicize or derail the process. The country’s entry into the eurozone serves as a reminder that hybrid interference, while potent and disruptive, does not inevitably determine outcomes—especially when political will and institutional continuity exist.
However, this is unlikely to mark the end of the struggle. If anything, the Kremlin’s focus on Bulgaria may intensify in the coming months. The country is expected to hold another snap election later this year, which will reopen opportunities for foreign influence and domestic destabilization. At the same time, pro-Russian actors such as Revival will seek to exploit any short-term difficulties associated with the transition to the euro—such as price adjustments, administrative friction, and public confusion—to validate their previous warnings and blame the EU.
In this sense, Bulgaria’s adoption of the euro is not just a political success but also a strategic test. Whether it strengthens public confidence in European integration or becomes another battleground for disinformation will depend on how effectively the Bulgarian government and EU institutions manage the transition and communicate its benefits. For now, however, Jan. 1 was a clear setback for Moscow’s ambitions to divide and weaken the EU. It is a signal that the EU’s gravitational pull remains formidable despite its contestation.
