A new European chapter for Gibraltar

Jamie Trinidad KC explains how the implementation of the UK-EU Agreement in respect of Gibraltar agreed by the UK and EU will affect both Gibraltar and Spain and the border between the two.

Brexit was widely regarded as a disaster in Gibraltar. In the 2016 referendum, 96% of Gibraltarian voters chose Remain, on a turnout of 84%. Gibraltar is British by political choice, but it is geographically and culturally European. Communities on both sides of the Gibraltar-Spain border – now an external border of the EU – depend on its fluidity for their livelihoods. This is not just a question of economics – many families and friendships straddle the border. Brexit therefore posed a unique set of problems, and there was little point viewing them through the ideological prisms of Westminster politics.

Gibraltar was excluded from the scope of the UK-EU Trade and Cooperation Agreement. A ‘Proposed Framework’ agreement concluded by the UK, Gibraltar and Spain on New Year’s Eve of 2020, hours before the end of the Brexit transition period, sketched the outlines of a post-Brexit settlement. However, converting that political understanding into a binding agreement between the UK and EU has taken several years of complex negotiations. The resulting UK-EU Agreement in respect of Gibraltar was signed in Brussels on 14 July 2026 and was applied provisionally (pending ratification) from the following day.

The Treaty contains hundreds of pages of dense legal text, but its central bargain is easy to understand. The physical barriers and routine immigration checks at the Gibraltar–Spain land border disappear, allowing people and goods to move across it far more easily. In return, Gibraltar (or, formally, ‘the UK, in respect of Gibraltar’) accepts substantial regulatory alignment with the EU. This includes rules protecting the integrity of the Schengen Area, and a customs union with the EU. Gibraltar’s services-based economy depends on some 15,000 frontier workers, most of whom are EU nationals, so the removal of restrictions at the border is a ‘win-win’.

Historically, the status of the border has dominated life in Gibraltar, shaping Gibraltarian identity itself. Spain, which has often used border restrictions as a political stick, closed the crossing completely in 1969. It was during the difficult closed-border years that Gibraltar joined the EEC with the UK in 1973, on special terms that excluded Gibraltar from, among other things, the Customs Union, VAT and the Common Agricultural and Fisheries Policies. The border reopened gradually between 1982 and 1985, shortly before Spain joined the EEC. For Gibraltarians who remember the years of enforced isolation, questions concerning border arrangements have profound emotional as well as economic significance.

The most controversial aspect of the Treaty settlement is the issue of EU (i.e. Spanish) officials conducting Schengen-facing border controls on persons who arrive in Gibraltar by air and sea. With the physical infrastructure of the border disappearing, the integrity of the Schengen area had to be protected at Gibraltar’s external points of entry. Under the Treaty, passengers arriving at the Gibraltar airport and port must therefore undergo both Gibraltar checks and Spanish Schengen checks. Maritime passenger volumes (excluding cruise passengers, who are generally exempt from Schengen checks) are tiny, so port arrivals are bussed to the airport border checkpoint.

The presence of Spanish officials exercising regulatory functions at the airport, while Spain continues to claim sovereignty over Gibraltar, is a bitter pill to swallow for many Gibraltarians, and prominent UK Brexiteers have described it as a ‘betrayal’. However, the Treaty expressly states that nothing in it affects the UK or Spanish legal positions on sovereignty or jurisdiction. Spanish and British border officers will perform their respective functions within a small ‘Joint Facility’ attached to the airport and located equidistantly in Gibraltar and Spain. Gibraltar remains outside both the EU and Schengen, so EU law is not directly applicable in Gibraltar. Where alignment is required, Gibraltar gives effect to the relevant rules through its own legal order, and the CJEU has no enforcement jurisdiction.

The Treaty arrangements differ radically from the status quo ante. Before Brexit, Gibraltar was inside the EU but outside the customs union and Schengen; now it is outside the EU but in a customs union with it and applying Schengen border rules. Gibraltar has lost valuable aspects of EU membership, such as participation in the single market for services. However, the Treaty offers new opportunities. Beyond the benefits of a free-flowing border, the Treaty opens the possibility of direct air links between Gibraltar and EU destinations, and provides a framework for cooperation in areas such as policing and the environment.

Neither Gibraltar nor Spain is a party to the Treaty, but both have played important roles in bringing it to fruition. A UK–Gibraltar Concordat records that the UK entered into its Treaty obligations with the Gibraltar government’s consent and following its ‘full participation’ in the negotiations. Gibraltar will carry much of the burden of implementation. And although the UK remains responsible for Gibraltar’s international relations, it has undertaken (‘other than in the most exceptional circumstances’) not to terminate the Treaty without either a three-quarters majority in Gibraltar’s Parliament or majority support in a Gibraltar referendum.

Regardless of the Concordat, democrats across the UK political spectrum ought to respect Gibraltar’s wishes regarding the continuing application of the Treaty, in line with the current UK government’s commitment to Gibraltar of ‘nothing about you without you’.

The fate of the Treaty also depends on Spanish cooperation and goodwill. Within four years of ratification, a committee appointed under the Treaty will submit a report evaluating its implementation, and if Spain asks the EU to terminate the Treaty in the light of that report, the EU must ‘take the necessary steps’ towards termination, ‘in accordance with its internal procedures’.

The success of this Treaty should be judged from the perspective of the people who are most affected by it. Gibraltar did not vote for Brexit, and its interests differ from those of the UK. Considering the actual choices available to Gibraltar – i.e. a hard external Schengen border, or a negotiated accommodation with its European neighbours – the Treaty settlement, for all its compromises, is vastly preferable to a no-deal scenario.

Ultimately, the Treaty does not restore what Gibraltar lost as a result of Brexit, but it does provide a solid foundation for Gibraltar’s future as an open, prosperous, European democracy.

By Professor Jamie Trinidad KC, Fellow of Wolfson College, University of Cambridge. He has advised the Gibraltar Government on aspects of the Treaty, but the views expressed here are personal.