Gibraltar is threatening legal action against the European Union over its decision to grant Spain a veto over the future of the Rock after Brexit.

The row over the Northern Ireland border, triggered by the Brussels negotiating paper published this week by Michel Barnier, mirrors the issues surrounding Gibraltar’s border with Spain. Spaniards who travel to Gibraltar every day for work will also be affected by any restrictions on the movement of citizens between the UK and the EU.

Brussels surprised Britain last year by giving Spain the power, under negotiating guidelines, to block any deal between the EU and the UK on the fate of Gibraltar. Since Britain insists that Gibraltar must leave on the same terms as the UK, the use of