Montenegro has taken new steps to address longstanding disputes with Croatia as it seeks to keep its European Union accession target on track for 2028. The disagreements, many linked to the wars that followed the breakup of Yugoslavia, could complicate the final stages of Montenegro’s membership negotiations if they remain unresolved.
Croatia has circulated an eight-point list of concerns to other EU member states, while Germany is urging both countries to reach a settlement. Montenegro’s recent legislative measures are intended to answer some of Zagreb’s demands, but Croatia has stressed that implementation will be essential before the issues can be considered closed.
Montenegro’s EU accession faces bilateral pressure
Montenegro is the leading EU candidate country in the Western Balkans and has set an ambition of joining the bloc in 2028. Its accession process requires progress across the negotiating chapters, followed by an accession treaty that must be approved and ratified according to EU and national procedures.
The disputes with Croatia are bilateral matters rather than new EU laws. However, they have become politically important because Croatia will eventually need to decide whether to support Montenegro’s accession treaty. Zagreb’s position is also being closely watched by other EU countries because unresolved disputes between member states and candidate countries can complicate enlargement.
Croatian Prime Minister Andrej Plenković said his government had raised the issues with Montenegro for years and argued that insufficient progress had been made recently. Croatia says it has supported Montenegro’s technical progress in the accession talks while seeking action on specific outstanding concerns.
Historical sites and the Morinj detention camp
One of the most sensitive disputes concerns the Morinj detention camp, which was operated by the Yugoslav People’s Army during the conflicts of the 1990s. Croatia wants a memorial plaque commemorating Croatian victims of the camp to remain protected.
Montenegro’s parliament recently adopted legislation concerning the protection of historical sites. The measure is intended to address Croatia’s concern that the memorial should not be removed or altered.
A related controversy involves a swimming pool in Kotor named after Zoran Gopčević, a water polo player who, according to allegations cited in the dispute, served as a guard shift commander at Morinj. Montenegro has passed separate legislation prohibiting sports facilities from being named after people who died less than 40 years ago. Because the measure applies retroactively, the pool’s current name would have to be removed: Gopčević died in 2000.
For Croatia, the practical application of these measures will matter as much as their adoption. Zagreb has indicated that laws must be implemented before the related concerns can be regarded as settled.
Missing victims and access to archives
Another issue concerns the whereabouts of the remains of 14 Croatian nationals who disappeared or died during the conflicts that accompanied the collapse of Yugoslavia.
Montenegro has asked Serbia for access to archives that could contain relevant information. Croatia has also made a request. The dispute is complicated by different accounts of where the victims were taken and where their remains may be located.
The archive believed to contain potentially useful records is in Belgrade. The victims did not die on Montenegrin territory, meaning Montenegro may not be able to resolve the matter alone. Nevertheless, Croatia wants Podgorica to assist in obtaining information that could be available without direct access to the Serbian archive.
Property compensation and the border dispute
Property rights are another unresolved part of the relationship. Croatia is seeking compensation for families who were unlawfully deprived of property. The two countries have reportedly agreed on the amount involved, but negotiations continue over the wording of the final agreement.
The countries also have a disagreement over their land and maritime boundaries. Only around 200 metres of the land border remain disputed, but Croatia wants Montenegro to abandon the possibility of arbitration on that section and focus instead on resolving the maritime boundary.
The border issue is not currently expected to block Montenegro’s EU enlargement path. Croatia itself retained a territorial dispute with Slovenia when it joined the EU in 2013. EU accession rules do not automatically resolve every bilateral border question, although disputes can become politically significant during the membership process.
Germany urges a swift settlement
Germany has entered the discussion by encouraging Croatia to avoid allowing bilateral grievances to derail Montenegro’s accession. Berlin is concerned that using unresolved disputes to delay one candidate could create a precedent for other Western Balkan countries seeking membership.
German Chancellor Friedrich Merz said the remaining bilateral issues could be solved and described Montenegro as having fulfilled the requirements identified by the EU, while negotiations continue on the final treaty. His intervention reflects the wider strategic importance attached to EU enlargement in the Western Balkans.
The European Union has repeatedly treated enlargement as a process based on reforms, legal alignment and the fulfilment of membership conditions. At the same time, accession requires political support from existing member states. That combination means bilateral relations can influence the final stages even where technical negotiations continue.
What happens next?
Croatia is expected to assess whether Montenegro’s new measures are fully implemented and whether outstanding agreements are completed. The most immediate areas to watch are:
- Implementation of the laws protecting historical sites and regulating the names of sports facilities.
- Further cooperation over records concerning the 14 missing Croatian victims.
- Final wording of the property compensation agreement.
- Continued talks on the land and maritime boundaries.
- Any change to the timetable for provisionally closing Montenegro’s negotiating chapters.
At a recent European Council summit, Croatia opposed wording referring to plans to provisionally close all of Montenegro’s accession chapters by the end of the year. That intervention demonstrated that the issue has moved beyond bilateral diplomacy and into the wider political debate over EU enlargement.
Why the dispute matters for Europe
The disagreement is important because Montenegro’s accession bid is being viewed as a test of how the EU handles bilateral disputes in its enlargement policy. Croatia wants recognition of unresolved wartime and property issues, while Germany is warning against a process in which individual grievances prevent broader progress.
For Montenegro, the challenge is to show that its laws produce concrete results and that it can address sensitive historical questions without derailing its European path. For Croatia, the priority is to demonstrate that the interests of victims and affected families are not overlooked.
There is no indication that Montenegro has joined the EU or that its accession treaty has been concluded. The 2028 objective remains a political target, and further negotiations, formal approval and national ratification would still be required before membership could take effect.
Montenegro’s latest measures may reduce tensions with Croatia, but the country’s EU membership bid will depend on implementation, continued bilateral dialogue and agreement across the EU’s enlargement process.
