On 7 August 1914, Britain requested that Japan destroy the German East Asia Squadron. On 15 August, Japan issued Germany an ultimatum demanding the handover of the Kiautschou Bay concession and that German ships abandon Chinese waters, thus intervening into World War I on the side of the Triple Entente. With the expiration of the ultimatum Japan officially declared war on Germany, blockading, besieging and eventually capturing Tsingtao. In September, the 1st and 2nd South Sea Squadrons proceeded to German New Guinea, where they occupied the German administrative centers in Rabaul, the Caroline Islands, Palau, Mariana Islands and Marshall Islands. The Japanese navy subsequently participated in the pursuit of the German East Asia Squadron through the Indian and Pacific oceans.