The United Kingdom and the European Union officially signed a treaty today regarding the status of Gibraltar, following an agreement reached last year aimed at easing border crossing measures and ending years of political uncertainty surrounding the British overseas territory.

The treaty was signed in Brussels by European Commissioner for Trade Maros Sefcovic, British Minister for Europe Stephen Doughty, Spanish Foreign Minister José Manuel Albares Bueno, and Gibraltar’s Chief Minister Fabian Picardo.

Under the agreement, Gibraltar residents will be able to cross into Spain using residence cards without requiring passport stamps, while Spanish citizens will be able to enter using government-issued identity cards.

Passengers arriving at Gibraltar Airport will present their passports to both Gibraltar and Spanish border officials. The UK also wants a similar system to be introduced for French police officers operating at London’s St Pancras railway station for the Eurostar service.

Britain gained control of Gibraltar — a strategically important territory located at the southern tip of Spain — through the Treaty of Utrecht, which ended the War of the Spanish Succession.