Slovenia to start implementing arbitration award on Saturday
Most laws adopted specifically for the purposes of the implementation of the arbitration award have already been passed, while the missing regulations, which deal with fisheries, are expected to be published in the Official Gazette today and enter into force on Saturday.
Slovenia considers the implementation of the arbitration tribunal's award an obligation under international law and has tried, unsuccessfully, to convince Croatia to participate in the implementation.
Croatia, which insists the arbitration procedure was compromised beyond repair despite the tribunal deciding it was not, has rejected the award and does not plan to implement it.
Slovenia has thus decided to go it alone; the way it plans to go about implementation is by asserting all aspects of sovereignty over its territory, whereby there are significant differences between the land and sea border.
Sea border
The majority of border clashes and incidents since 1991 have been at sea, and it is widely expected this will be the main area where border disputes may flare up yet again.
The arbitration tribunal awarded Slovenia 80% of the bordering Bay of Piran, Slovenia having previously considered the entire bay under its jurisdiction.
The tribunal also determined a junction area, a corridor of sorts that is 2.5 nautical miles wide and reaches from Slovenian territorial waters to the high sea.
Slovenia plans to assert its sovereignty in the 80% of the Bay of Piran, which is designated as internal waters, and the entirety of the territorial waters as circumscribed by the old border with Italy in the north and the borders determined by the arbitration tribunal's ruling in the south.
Since the tribunal determined the border as a series of coordinates, Slovenia considers it directly enforceable given that there is no need to set any border markers in cooperation with Croatia, it is enough to merely draw the line into maps and official records.
Slovenia has done so with the act on the recording of the border, which after 30 December will trigger a series of administrative procedures leading to the border line being described in all official databases and registers.
Land border
The situation on land is slightly different: in the few disputed points, the arbitration tribunal merely described the plots of land which will change hands, whereby the border is yet to be precisely delineated on the ground.
Slovenia has urged Croatia to appoint officials to a joint commission on border delineation as instructed by the arbiters, but Croatia has refused to do so given that it disputes the very core of the arbitration procedure.
While the act on the recording of the border will thus set into motion procedures for the entry of individual plots into databases such as the land register or the land cadastre, the actual border on the ground will not be determined until Croatia decides to join the process.
Exercise of sovereignty
Given the different starting points, the way Slovenia exercises sovereignty will differ slightly on land and sea, according to unofficial information.
At sea it will do so by virtue of police controlling the territorial waters, and by exercising jurisdiction over fisheries, the only commercial activity conducted in earnest in this part of the Adriatic.
What this means is that Croatian fishermen will be allowed to fish in Slovenian waters, as determined in Croatia's EU accession treaty, which stipulates that up to 25 Croatian fishing boats may catch up to 100 tonnes of fish in Slovenian waters annually.
However, they will need to apply for Slovenian permits; if they do not, they will be fined by the fisheries inspection, having so far only been issued warnings.
Passage of fishing boats will not be deemed an infringement, it is only when the boats actually catch fish that they require permits.
At land this means initially recording the previously unrecorded properties in official registries and then exercising administrative control through taxes and levies, and various inspectorates.
Potential points of contention
Even though officials have been very vocal about stressing that Slovenia will refrain from causing or instigating any incidents, and unofficial information indicates there are no plans to beef up police presence at sea, history suggests incidents at sea may be expected.
In the past six months alone Slovenian authorities recorded well over 1,000 "events" in seas now considered Slovenian, of which many involved Croatian police boats, according to media reports.
Officially only events involving police or military vessels will henceforth be considered incidents, any events involving just commercial boats will be classified as infringements punishable with fines.
But in the past Croatian police often came to aid Croatian fishermen, which occasionally created tensions and flare-ups at sea.
Another possible point of contention is a Croatian-owned mussel farm, which after the tribunal's ruling is mostly located in Slovenian territorial waters, though a part of it will be in Croatian seas.
Not only is it located in an area that is not designated for mussel farming in Slovenian legislation, it is already the subject of ongoing administrative proceedings in Slovenia.
On land the main possible point of conflict is Trdinov vrh (Sveta Gera in Croatian), a strategically important peak on which there is a Slovenian military installation.
The portion of the peak containing the military installation has been awarded to Croatia and Slovenia plans to honour the arbitration award and hand it to Croatia.
However, Prime Minister Miro Cerar has said Slovenia is only willing to do so in line with official handover procedure for military installations.
Croatia is unlikely to consent since it would constitute admission of the tribunal's award; unofficial information suggests Slovenian troops will stay at the installation until a formal handover is made, which from Slovenia's perspective would mean that it would have a military installation on the neighbouring country's territory.
Life along the border
Things will also change for about 100 Slovenian citizens living along the border whose homes will henceforth be on Croatian soil.
Slovenia has adopted special laws and regulations to help them with issues such as taxes, health insurance and pensions. It will partially finance relocation for those who may want to move, but these steps will not be taken immediately.
The affected people have one year to decide whether they want to relocate, and three years to complete the move.
Unofficial information suggests many initially expressed their desire to move, but some of them have since changed their mind. The final number will not become clear until the one-year term has passed.
International implications
Beyond the immediate implications for life along the border, the implementation of the arbitration tribunal's award marks the formal beginning of Slovenia's activities to use legal means to force Croatia to comply with the award.
The government has said that if Croatia continues to ignore the arbitration award, it will take it to the EU Court of Justice over infringement of international law.
Slovenia considers the arbitration agreement a part of international law and violations thereof as infringements of international law.
Additionally, Slovenia could claim violation of Croatia's EU accession treaty, in which fisheries rights along the border are specified.
Foreign Minister Karl Erjavec has said legal proceedings could be triggered early in 2018.
Slovenia is also counting on the EU Commission, which has said the arbitration tribunal's award needs to be respected and tasked Frans Timmermans, the vice-president, with facilitating the implementation of the award.
Unofficial information indicates Timmermans is already drawing up a plan on how to proceed with his task.