Brussels – After almost 14 years of negotiations – and counting – work on drafting Montenegro’s EU Accession Treaty officially began on 13 May. For months, intense discussions have surrounded this long-awaited milestone in the EU enlargement process, not seen since Croatia signed its own Accession Treaty in 2011. Since then, major positive and negative developments have reshaped this EU policy. There is little doubt that the final stage of Podgorica’s accession is about far more than Montenegro alone.

“If Montenegro successfully negotiates an Accession Treaty that combines full membership with stronger accountability and safeguard mechanisms, this could very well become the template for future enlargements” – not only for the Western Balkans, but potentially also for Ukraine and Moldova – explain Jovana Marović, former Deputy Prime Minister and Minister for European Affairs of Montenegro in 2022, and Odeta Barbullushi, Resident Professor at the College of Europe, speaking with The New Union Post.
Drawing on their policy brief on how Accession Treaties can strengthen Europe, the two members of the Balkans in Europe Policy Advisory Group (BiEPAG) highlight that “the EU is clearly searching for a new enlargement model”, and that Montenegro could become “the first example” of how to reconcile Brussels’ two most pressing objectives. On the one hand, the EU wants “enlargement to remain credible and geopolitically effective”. On the other, it needs “to avoid repeating past mistakes where reforms slowed down or were reversed after accession.”
This is where Montenegro’s accession process takes on “a broader strategic significance beyond the country itself.” As the most advanced candidate in the accession process – and the only one with an established Ad Hoc Group for Drafting the Accession Treaty – Podgorica finds itself in the position of representing “the first enlargement case taking place after the EU’s experience with democratic backsliding in some member states,” they note.
While a treaty-based system with “clearer benchmarks, incentives and consequences” could make the process more predictable and rules-based for both sides – the current Union and candidate countries – the two analysts make clear that this model would only work “if it remains genuinely connected to full membership.” On the contrary, if safeguards in this new kind of Accession Treaty become “so extensive that enlargement begins to resemble permanent probation, the process risks losing its transformative power.”
From pre-accession conditionality to post-accession enforcement
Montenegro has all the credentials to become the first country where the EU “genuinely” tries to bridge the gap between pre-accession conditionality and post-accession enforcement. “The key issue is not whether reforms are adopted before membership, but whether they remain durable after accession, when EU leverage traditionally weakens,” Marović and Barbullushi point out.
The most important safeguard mechanisms that can be introduced during the Accession Treaty drafting phase are those that are “automatic, measurable and directly linked to consequences.” Following the last waves of enlargement over the past 20 years, the EU has learned that monitoring alone – through annual reports and political dialogue – may not be enough to prevent or reverse democratic backsliding once a country becomes a member state.
For this reason, a new generation of Accession Treaties should contain “concrete enforcement clauses tied to rule-of-law benchmarks”, especially regarding judicial independence, anti-corruption enforcement, prosecutorial autonomy, media freedom and merit-based public administration. In the event of “serious regression” in these areas, the EU should have the possibility to “temporarily suspend access to certain funds, programmes, agencies, or specific benefits connected to the internal market“, the two analysts explain.

Considering that, in today’s European Union, the rule of law is not only a domestic governance issue but also directly affects the functioning of all these aspects of the EU as a whole, new safeguards in the Accession Treaties “should not be understood as punitive instruments, but as tools for preserving trust inside the Union.” This precise concept was also recently reaffirmed by Commissioner for Enlargement Marta Kos.
According to Marović and Barbullushi, Accession Treaties could become the “missing link” between pre-accession conditionality and post-accession enforcement – rather than a “sharp dividing line” – if the EU is able to draw three major lessons from previous enlargements.
First, “reforms achieved under strong accession pressure are not necessarily irreversible.” While candidate countries are highly motivated during negotiations – as membership is “the ultimate incentive” – after accession, “that leverage declines dramatically.” The EU assumed that democratic consolidation would become self-sustaining once countries entered the Union, and in some cases that assumption proved overly optimistic.
Second, “the EU relied too heavily on political monitoring mechanisms without sufficiently credible enforcement tools.” For example, the two analysts note that the experience with the Cooperation and Verification Mechanism in Bulgaria and Romania showed that monitoring can produce transparency, but transparency alone does not guarantee compliance “if there are no material consequences attached to non-compliance.”
Third, Article 7 of the Treaty on European Union (TEU) – the procedure allowing the suspension of certain rights of a member state in the event of a serious breach of the values enshrined in the Treaties – “demonstrated the limits of peer pressure inside the EU.” Once democratic backsliding becomes politically entrenched, it can be “extremely difficult” for the Union to react effectively “because enforcement mechanisms are too politicised and institutionally cumbersome.”
All things considered, the broader lesson is that EU enlargement policy “can no longer be based solely on optimism about convergence,” but must also include institutional safeguards “capable of protecting democratic standards over time.”
A new generation of Accession Treaties
As already seen with instruments such as the Growth Plan for the Western Balkans – which links the disbursement of EU funds to the implementation of rule-of-law reforms – there is increasing awareness in Brussels that financial conditionality can be more effective than political declarations, as it “creates tangible incentives and tangible costs”, Marović and Barbullushi stress.
Applied to the EU accession process, the key principle of a new generation of Accession Treaties is that EU financial support should be more performance-based. “Funding should increasingly depend not only on adopting reforms, but on demonstrating credible implementation and institutional resilience over time.”
The two BiEPAG members argue that the sectors to be more directly linked to EU funding are those “where political resistance to reform is strongest” and where formal compliance is easiest to simulate “without producing real institutional change.” This includes the judiciary, anti-corruption institutions, prosecution services, public procurement, state aid control, media freedom and public administration reform. In these areas, governments can adopt legislation relatively quickly, but implementation often remains “selective or politically controlled.”
In practical terms, they suggest that judicial reform should not be measured solely through legal amendments, but also through track records – such as transparent appointments, final convictions in high-level corruption cases, protection from political interference, and institutional independence in practice.

A similar approach should be applied to public procurement – which directly affects both corruption risks and the functioning of the EU internal market – as well as to media freedom and independent regulators, given that democratic backsliding often begins with the weakening of oversight institutions and the concentration of political influence over public discourse.
In any case, there is no doubt that full membership must remain the core element of any Accession Treaty, rejecting suggestions such as temporarily limiting voting rights.
As Marović and Barbullushi warn, “there is definitely a risk that differentiated integration could gradually evolve into a new model of second-tier membership if it is not designed carefully.” It is true that the EU already operates with different levels of integration among current member states – the Eurozone, the Schengen area, Treaty opt-outs – but the real danger emerges if temporary differentiation becomes politically permanent.
EU enlargement policy has historically worked because candidate countries were offered a clear promise of full and equal membership. “If that promise becomes diluted into a model where some states remain excluded from key decision-making areas, the credibility and transformative power of enlargement could weaken significantly,” they caution.
Moreover, there is also a geopolitical dimension to take into account. “In the Western Balkans, ambiguity and delays already create frustration and space for external influence.” In other words, if future enlargement is perceived as offering only partial integration without genuine equality, “public support for EU reforms may decline.”



























