Under the terms of the Peace of Utrecht 1713 (which ceded the territory of Gibraltar to the British Crown in perpetuity) and the preambles to the 1969 and 2006 Constitutions of Gibraltar, the guarantee given to the Gibraltarian people by the British Government is that they will only become Spanish subjects if they freely and democratically express their desire to do so, which they are highly unlikely to do at any time in the foreseeable future. Most recently, the Gibraltar Government held a referendum on the subject in 2002, where the concept was decisively rejected by the Gibraltarian people, and as a corollary the British Government now refuses to discuss the topic of sovereignty without the consent of the Gibraltarians.
Spain’s position on Gibraltar, without relinquishing their ultimate claim to sovereignty, has become more conciliatory in recent years, and in September 2006, a communique was issued by a Tripartite Forum attended by Miguel Angel Moratinos, Spanish Minister for Foreign Affairs, Geoff Hoon, UK Minister for Europe and Peter Caruana, Chief Minister of Gibraltar, which is commonly known as the Cordoba Agreement. This contained a package of agreements designed to improve day-to-day relations between Spain and Gibraltar, adopted without prejudice to the respective Governments’ positions on sovereignty and jurisdiction.
Far from being politically unstable, therefore, Gibraltar has legal and political reasons in terms of its relationship with Britain and Spain to consider itself safe from anything other than an act of aggression from the Spanish government, which is obviously unthinkable in the context of those relationships.