When World War I began, Germany invaded neutral Belgium and Luxembourg as part of the Schlieffen Plan, in an attempt to capture Paris quickly by catching the French off guard by invading through neutral countries. It was this action that technically caused the British to enter the war, as they were still bound by the 1839 agreement to protect Belgium in the event of war. On 2 August 1914, the German government demanded that German armies be given free passage through Belgian territory, although this was refused by the Belgian government on 3 August. The King Albert I addressed his Parliament on 4 August, saying "Never since 1830 has a graver hour sounded for Belgium. The strength of our right and the need of Europe for our autonomous existence make us still hope that the dreaded events will not occur." The same day German troops invaded Belgium crossing the frontier at dawn. Liège was attacked on 4 August and fell on 7 August.