ザクセン＝コーブルク＝ゴータ家
Both states shared membership of NATO. And both countries were member states of the European Union, however, the UK left the EU on 31 January 2020. In addition, both countries' royal families are descended from the House of Saxe-Coburg and Gotha, with the British branch being known as the House of Windsor and the Belgian branch as the House of Belgium.